# Questions Asked onFebruary 28, 2010

1. ## chemistry

A student placed 19.0g of glucose (c6h12o6) in a volumetric flask, added enough water to dissolve the glucose by swirling, then carefully added additional water until the 100ml.- mark on the neck of the flask was reached. The flask was then shaken until

2. ## Chemistry

Write and balance equations for the following reactions. A)Iron metal and Chlorine gas react to form solid iron(III) chloride. B)Solid aluminum carbonate decomposes to form solid aluminum oxide and carbon dioxide gas. C)Solid magnesium reacts with aqueous

3. ## Chemistry

What two components gain heat when ice is added to water? Express it mathematically. (use appropriate symbols, not your actual numerical values. - I know that the ice gains heat as well as the H2O from the ice, but i don't understand how to express it in

4. ## chemistry

How long will it take for 25% of the C-14 atoms in a sample of C-14 to decay? The half-life for the radioactive decay of C-14 is 5730 years. If a sample of C-14 initially contains 1.1 mmol of C-14 , how many millimoles will be left after 2275 years?

5. ## College Chemistry

Calculate the heat of formation reaction for SiO2(s)+4HF(g) --> SiF4(g)+2H2O(l) I got -129.6 and it says I'm wrong

6. ## Chem--buffers

Explain why a mixture formed by mixing 100 mL of 0.100M CH3COOH and 50 mL of 0.100M NaOH will act as a buffer? in adittion to this, how do you identify if a an aqueous solution is a buffer solution, such as a solution with an acid and a base, but no common

7. ## Chemistry

A student heats 5.128g of the sodium carbonate/sodium bicarbonate mixture to a constant mass of 4.256g. Determine the mass of sodium bicarbonate present in the mixture.

8. ## Math--Exponential Functions

Suppose an investment of \$500 doubles in value every 15 years. How much is the investment worth after 30 years? After 45 years? please help!!! i don't even understand how to approach this problem! =(

9. ## Chemistry

How many molecules of BrF2 form when 384g Br2 react with excess F2? equation: Br2 + 5F2 ---> 2BrF5 I really just need the guidelines to figure out the problem, i can figure out the rest from there. Please and thank you.

10. ## Chemistry

If the initial concentration of is 0.250 , and the reaction mixture initially contains no products, what are the concentrations of and after 80 ?

11. ## physics

A charge of 1.5uC is placed at the origin, and a charge of 3uC is placed at x = 1.5m. Locate the point between the two charges where the electric field is zero? Q1 P Q2 x------------*-----------. 0

12. ## Physics

Three blocks of masses 1.0, 2.0, and 4.0 kilograms are connected by massless strings, one of which passes over a frictionless pulley of negligible mass, as shown above. Calculate each of the following. a. The acceleration of the 4 kilogram block b. The

13. ## physics

How long will it take a 230 W motor to lift a 335 kg piano to a sixth-story window 19.0 m above?

14. ## Chemistry

How many moles of oxygen will occupy a volume of 2.5 liters at 1.2 atm and 25 degrees celcius

15. ## chemistry

1.Use the Vsepr theory to predict and explain the shape and bond angle of each of the molecules SCI2 and C2CL2. 2.Deduce whether or not each molecule is polar, giving a reason for your answer...Any help please??

16. ## college physics

A 1300 kg car rolling on a horizontal surface has speed v = 65 km/h when it strikes a horizontal coiled spring and is brought to rest in a distance of 2.9 m. What is the spring stiffness constant of the spring?

17. ## chemistry

Write Skeleton equations for these reactions. A) Heating Copper(II) sulfide in the Presence of diatomic oxygen produces pure copper and sulfur dioxide gas. B)When heated, baking soda (Sodium hydrogen carbonate) decomposes to form the products sodium

18. ## Trig

What is the exact value of cot(4pi/3)? Do not use a calculator.

19. ## Chemistry

Balance the following equations. A) SO2 + O2 --> SO3 B)Fe2O3 + H2 --> Fe +H2O C)P + O2 -->P4O10 D)Al + N2 --> AlN

20. ## physics

an athlete has a large lung capacity of 7.0L. Assuming to be an ideal gas how many molecules of air are in the athletes lungs when the air temperature in the lungs is 37 degrees celcius under normal atmospheric pressure.

21. ## physics

A toaster uses a Nichrome heating wire. When the toaster is turned on at 20°C, the initial current is 1.50 A. A few seconds later, the toaster warms up and the current has a value of 1.20 A. The average temperature coefficient of resistivity for Nichrome

22. ## chemistry 106

Nitroglycerin, an explosive compound, decomposes according to the equation below. 4 C3H5(NO3)3(s) 12 CO2(g) + 10 H2O(g) + 6 N2(g) + O2(g) Calculate the total volume of gases when collected at 1.2 atm and 25°C from 1.3 multiplied by 102 g of nitroglycerin.

23. ## physics

A 275 kg load is lifted 24.0 m vertically with an acceleration a=0.120 g by a single cable. Determine the tension in the cable.

24. ## Physics

If you are standing on the edge of a canyon and yell into the canyon, how long will it take the echo to return to you if the opposite canyon wall is 1060.4 m away and the air temperature is 25.2 C?

25. ## physics

Having trouble with this one: A capacitor having a capacitance of 10uF is charged by 100v battery. A.)Calculate the charge on the capacitor? B.)calculate the energy stored in the capacitor? C.) the terminals of the capacitor is now disconnected from the

26. ## Statistics

The Gibbs Baby Food Company wishes to compare the weight gain of infants using their brand versus their competitor’s brand. A sample of 40 babies using the Gibbs products revealed a mean weight gain of 7.6 pounds in the first 3 months after birth. The

27. ## Precalculs

I have no idea how to do these type of problems. -------Problem-------- Solve each equation on the interval 0 less than or equal to theta less than 2 pi 42. SQRT(3) sin theta + cos theta = 1 ---------------------- There is an example prior to the

28. ## science

how do we know a song thrush must have ears???

29. ## physics

a horizontal force of 95 N is applied to 60 kg crate on rough , level surface. if crate accelerates at 1.20 m/s2 , what is magnitude of the force of kinetic friction acting on the crate?

30. ## college

TiO2(s) + H2(g) Ti(s) + H2O(g) (a) Consider the unbalanced equation above. What is the maximum mass of titanium that can be produced when 2.65 g of TiO2 and 3.40 g H2 react? = ?g Ti (b)Assume the reaction in part (a) goes to completion. Calculate the mass

31. ## Chem

The hydrolysis of sucrose into glucose and fructose in acidic water has a rate constant of at 25 degrees C. Assuming the reaction is first order in sucrose, determine the mass of sucrose that is hydrolyzed when 2.60 L of a 0.150 M sucrose solution is

32. ## chemistry

how much heat will be released if 30 grams of octane is burned in excess oxygen?

33. ## physics

How much work must be done to stop a 1200 kg car traveling at 135 km/h?

34. ## chemistry

Give the percent yield when 15.9 g of CO2 are formed from the reaction of 4.000 moles of C8H18 with 4.000 moles of O2. 2 C8H18 + 25 O2 -> 16 CO2 + 18 H2O

35. ## Math

John's car is 13 feet long. He is making a model that is 1/12 of the actual size. Which proportion below should be used to find the length, L, of the model? A(wrong) 13/L = 1/12 B(correct) L/13 = 1/12 C(wrong) L/13 = 1/L D(wrong) 12/L = 13/1 I don't get

36. ## physics

how long does it take a 19kW steam engine to do 6.8x10^7 J of work?

37. ## Science - Optics

A lens has a magnification of +2.0 and if the focal length is +10 find the impage position and the object position. The type of lens is a diverging lens, but how do i find the di and the do if nothing else is given?

38. ## precalculus

The question is...find the radian measure of the central angle of a circle of radius r that intercepts an arc of length s. Then it gives the radius r of 27 inches and an arc length s of 6 inches. How do I do that?

39. ## chemistry 106

The pressure of 6.0 L of an ideal gas in a flexible container is decreased to one-half of its original pressure, and its absolute temperature is decreased to one-seventh of the original. What is the final volume of the gas?

40. ## Science

What are the similarities and differences of static and current electricity?

41. ## Chemistry

CS2(g) + O2(g) CO2(g) + SO2(g) (a) Consider the unbalanced equation above. What is the maximum mass of SO2 that can be produced when 46.0 g of CS2 and 29.0 g O2 react? (b) Assume the reaction in part (a) goes to completion. Calculate the mass of excess

42. ## calculus

The limit represents the derivative of some function f at some number a. Select an appropriate f(t) and a. lim_(t->1)(t^3+t-2)/(t-1) 1f(t) = t^3, a = 1 f(t) = t^3 + t, a = 1 f(t) = t - 2, a = 1 f(t) = t - 2, a = -1 f(t) = t^3 + t, a = -1 f(t) = t^3, a = -1

43. ## probability

A bag contains 3 red chips, 2 blue chips, and 1 white chip. If 2 chips are chosen from the bag (without replaceent), determine the probability that they are of different colors.

44. ## math

Tom is a habitual shopper at garage sales. Last Saturday he stopped at one where there were several types of used building materials for sale. At the low prices being asked, Tom knew he could resell the items in another town for a gain. Four things stood

An empty trailer has a mass of 850 kg. When the trailer carries a load, its mass is 1.4 t. What is the mass of the load?

46. ## statistics

7. A sample of 40 observations is selected from one population. The sample mean is 102 and the sample standard deviation is 5. A sample of 50 observations is selected from a second population. The sample mean is 99 and the sample standard deviation is 6.

47. ## physics

A toy car with a mass of 120 g moves to the right with a speed of 0.56 m/s. A small child drops a 25.0-g piece of clay onto the car. The clay sticks to the car and the car continues to the right. What is the change in speed of the car? Consider the

48. ## Accounting

I have almost completed my assignment, but am stuck on this question. I researched my text and other outside sources and can't seem to find the answer. Can anyone provide any guidance on this for me? What are the strengths and weaknesses of the various

49. ## economics

Assume that a bottle of wine sells for \$10. The government decides to put a \$1 per bottle tax on wine. What will be the new price that consumers must pay for a bottle of wine?

50. ## Chemistry

What is the pH of a solution containing 0.10 M propanoic acid (HC3H5O2) and 0.10 M sodium propanoate after 0.02 mol of HCl is added to 1.0 L of the solution?

1) Use the cofunction identites to evaluate the expression without the aid of a calculator. cos^2 18 degrees + cos^2 72 degrees.

52. ## English

1. He is one of the tallest boys in my class. 2. He is one of the tallest boys in our class. (Are both the same?) 3. He got three times as much money as I. 4. He had three times as much money as I. 5. He earned three times as much money as I. (Does #3 mean

53. ## Science

1) How much more energy is released in a 5.0 magnitude earthquake than a 4.0 magnitude earthquake. I know that each unit of Richter magnitude equates to roughly a 32-fold energy increase and that the amplitude has a tenfold increase but I am still confused

54. ## Math

A flock of geese is flying while another goose is flying past it. The goose asks the leader of the flock how many they are. The leader answers: "Us, plus us, plus half of us, plus a quarter of us, plus myself make the flock 100 geese. How many are we?

55. ## physics

If a particle of mass 5.7 kg is moving east at 10 m/s and a particle of mass 19 kg is moving west at 10 m/s, what is the velocity of the center of mass of the pair? Give answer is m/s to the west. I tired to use: Vcm = mv/M. I plugged in (5.7)(10) +

56. ## chemistry

For the reaction A to products}, the following data were obtained: t=0 s, A}]=0.715 M; 22 s, 0.605 M; 74 s, 0.345 M; 132 s, 0.055 M. What is the half-life of the reaction? ive been posting this for awhile now...can someone just show me how to go about

57. ## math

the radii of three concentric circles shown are in the ratio 1:2:3. What is the probability that random shot that hits the target will hit inside the second circle but inside the innermost circle?

58. ## Statistics

8. A sample of 65 observations is selected from one population. The sample mean is 2.67 and the sample standard deviation is .75. A sample of 50 observations is selected from a second population. The sample mean is 2.59 and the sample standard deviation is

59. ## Edit plz!

can u edit this small paragraph plz? thnx! Have you ever thought of your goals and skills that you would like to improve. There are 3 skills that I want to improve this semester. They are communication, problem solving, and time-management. Communication

60. ## chemistry

For the reaction A to products}, the following data were obtained: t=0 s, A}]=0.715 M; 22 s, 0.605 M; 74 s, 0.345 M; 132 s, 0.055 M. What is the half-life of the reaction?

61. ## physics

A 22.1 kg child descends a slide 3.4 m high and reaches the bottom with a speed of 2.4 m/s. How much thermal energy due to friction was generated in this process? I'm sure where to even start this problem

62. ## Pre-Cal

Perform the addition or subtraction and use the fundamental identities to simplify. tan x - sec^2 x / tan x I do not know where to start.

63. ## statistics

A medical statistician wanted to examine the relationship between the amount of sunshine (x) and incidence of skin cancer (y). As an experiment he found the number of skin cancers detected per 100,000 of population and the average daily sunshine in eight

64. ## English

Expand these notes into fluent sentences. Vary the length and pattern of your sentences and avoid 'then' and 'so'. Try not to use 'and' more than once. girl went to night club-proud of new ring-worth 500-ring loose on her finger-ring fell off-not noticed

65. ## Chemistry

What mass of CO2 could be absorbed by 1.34 g of CaO?

66. ## calculus

why is lim of tanx as x approaches to (pie/2)+ is negative infinity. Shouldnt it be positive infinity since pie/2 is approaching on the right

67. ## Math

Carmen can type 18 words in 27 seconds. How many words can she type in 60 seconds?

68. ## To jhon, jackie, jill, sandra, mariam or whoever

Your posts have been removed. Once you write up YOUR THOUGHTS, please re-post, and someone here may be able to help.

69. ## Chemistry

What is the maximum mass of product that can be formed when 76.0 g of solid zinc and 17.5 g nitrogen gas react?

70. ## biology can someone check

1) What phase are daughter cells in as a result of mitosis? answer: Anaphase 2)During what phase of mitosis do centromeres divide and the chromosomes move toward of their respective poles? answer: prophase 3)Which phase of mitosis is the last phase that

71. ## chemistry

The reaction A to products is first order in A. 1.) If 2.00 g A is allowed to decompose for 42 min, the mass of A remaining undecomposed is found to be 0.50 g. What is the half-life, t_{1/2}, of this reaction? 2.)Starting with 2.00 g A, what is the mass of

72. ## phyics

on a warm day(92 degrees F) an air filled balloon occupies a volume of .20m^3 and is under a pressure of 20.0 lbs/in^2. if the baloon is cooled to 32 degrees F in a refigerator while its pressure is reduced to 14.7 lb/in wat is the volume on the air in the

73. ## geography

a mountain is to a ski jumper as a what is to a diver

74. ## Math

An electric train moves in a northerly direction at 100 km an hour. The wind blow in an easterly direction at 50 km per hour. In which direction does the smoke go?

75. ## ap us history

the questionsa are about the Truman Doctrine 1)To what extent were we able to carry out our foreign policy aims? 2)To what extent do recent events in the former Soviet Union suggest that the US may have operated under false assumptions in the years

76. ## Chemistry- Stoichiometry

How many molecules of BrF2 form when 384g Br2 react with excess F2? equation: Br2 + 5F2 ---> 2BrF5 I really just need the guidelines to figure out the problem, i can figure out the rest from there. Please and thank you.

77. ## HRM/240

letter recommending to a company's board of directors that affirmative action policies be implemented Include points supporting the recommendation and clearly address points that may be used against this recommendation. The letter must also address how

78. ## Physics

A rocket is launched straight up with constant acceleration. Four seconds after liftoff, a bolt falls off the side of the rocket. The bolt hits the ground 6.50 s later.

79. ## chemistry

Calculate the boiling point elevation of a solution containing 22.8 g of glucose (C6H12O6) dissolved in 672.0 g of water. Calculate the freezing point depression for the same solution.

80. ## chemistry

Calculate the boiling point elevation of a solution containing 22.8 g of glucose (C6H12O6) dissolved in 672.0 g of water. Calculate the freezing point depression for the same solution.

81. ## chemistry

What mass in g of NaCl is formed from the reaction of 54.0 mL of a 0.078 M AgC2H3O2 solution with 71.0 mL of 0.109 M MgCl2 solution? 2 AgC2H3O2 (aq) + MgCl2 (aq) --> 2 AgCl (s) + Mg(C2H3O2)2 (aq)

82. ## Chem- follow up question

Sorry i posted this as an answer after my question had been answered, this is continued from the qualitative analysis question: That reallly cleared some things up, but I do still have a few questions. Umm im not completely clear on the hyrogen peroxide

83. ## geography

A skull is to rowing as a what is to yachting

84. ## math

A right rectangle and a right triangle prism have the same height. If the lenght of the side of the rectangle base is twice the width, explain how to determine the area of the triangular base in terms of the rectangle base length.

85. ## math

Give the equation of a line perpendicular to the line y = -8x + 8 having the y-intercept 2 units below the y-intercept of the given equation. At what point the two equations cross each other?

86. ## Physics

h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 6 7 3 9 3 5 9 3 ok heres the problem in a picture h t t p : / / i m g 1 9 2 . i m a g e s h a c k . u s / i m g 1 9 2 / 4 5 0 0 / c a p t u r e x x w . j p g ok I called the 4 kg

87. ## chemistry

The reaction A + B to C + D is second order in A and zero order in B. The value of k is 1.10×10−2 M^{-1}\;min^{-1}. What is the rate of this reaction when A}]=0.124 M and B}]=3.89 M?

88. ## chemistry 106

A gas-filled balloon having a volume of 1.50 L at 1.2 atm and 25°C is allowed to rise to the stratosphere (about 30 km above the surface of Earth), where the temperature and pressure are -23°C and 3.00 multiplied by 10-3 atm, respectively. Calculate the

89. ## chemistry 106

calculate the pressure exerted by 1.00 moles of CO2 confined in a volume of 5.00 L at 450. K. Compare the pressure with that predicted by the ideal gas equation.

90. ## science

frogs have ears on the side of their head.what can they hear in the water?

91. ## college physics

A 22.1 kg child descends a slide 3.4 m high and reaches the bottom with a speed of 2.4 m/s. How much thermal energy due to friction was generated in this process? I'm not sure where to even start this problem. Please help.

92. ## chemistry

For the reaction A to products}, the following data were obtained: t=0 s, A}]=0.715 M; 22 s, 0.605 M; 74 s, 0.345 M; 132 s, 0.055 M. What is the half-life of the reaction?

93. ## English

How do i balance this sentence? Is it already balanced? Tubman wanted freedom regardless of personal danger, whereas for her husband,john,personal safty was more important than freedom.

94. ## math

A: Solve the following equation: k2 + 4k = 0 A: By factoring B: By using the quadratic formula D: Do the results in A, B, differ from each other? Why or Why not?

95. ## calc plzzzz help

This limit represents the derivative of some function f at some number a. Select an appropriate f and a. lim_(h->0) (root4(256+h)-4)/h 1 f(x) = x^4, a = 4 f(x) = x^1/4, a = 4 f(x) = x^1/4, a = 256 f(x) = √x, a = 256 f(x) = √x, a = 16

96. ## history

how did the factors of population,economics,disease and climate shape the basic social conditions and ways of life in both the south and new england?

97. ## economics

Best Answer - Chosen by Voters Simply put, the higher the CR the more monopolistic an industry is (or in this case oligopolistic). The 4 firm concentration ratio is usually the standard measure of this. In the example w/ 30% CR you can assume there are

1-What phase are daughter cells in as a result of mitosis? -Anaphase 2- During what phase of mitosis do centromeres divide and the chromosone-mes move toward their respective poles? -prophase 3- Wchich phase of mitosis is the last phase that chromatids are

99. ## math

How can I construct a stem and leaf plot with the midterm test scores of the seventh-period typing class with the list below? 77, 93, 91, 74, 65, 68,97, 88,59,74, 83, 85, 72, 63, 79

1) Use the cofunction identites to evaluate the expression without the aid of a calculator. cos^2 18 degrees + cos^2 72 degrees. Would I use the forumula cos(pi/2 - Q) = sin Q

101. ## Chemistry

How many molecules of BrF2 form when 384g Br2 react with excess F2? equation: Br2 + 5F2 ---> 2BrF5 I really just need the guidelines to figure out the problem, i can figure out the rest from there. Please and thank you.

102. ## biology

1) What phase are daughter cells in as a result of mitosis? answer: Anaphase 2)During what phase of mitosis do centromeres divide and the chromosomes move toward of their respective poles? answer: prophase 3)Which phase of mitosis is the last phase that

103. ## English

I have to find five poetic devices in this poem. Can you please help me? Weekend Glory Some clichty folks don't know the facts, posin' and preenin' and puttin' on acts, stretchin' their backs. They move into condos up over the ranks, pawn their souls to

104. ## Algebra 2

solve the equation: log(base2)^(x-3)log(base2)^5 = 2log(base2)^10 I don't know how to solve it, can someone help me? Please and thank you.

105. ## English

1. I have as many books a Tom has. 2. I have as many books as Tom does. 3. I have as many books as Tom. 4. I have as many books as Tom has many books. (Which ones are correct?) 5. Tom has as much money as Bill. 6. Tom has half as much money as Bill. 7. Tom

106. ## Physics

Thank you for answering my previous questions! I have another one now in regards to the following question... An unknown potential difference exists between the inner and outer surfaces of the membrane of a cell. The inner surface is negative relative to

107. ## BIOLOGY

1) What phase are daughter cells in as a result of mitosis? answer: Anaphase 2)During what phase of mitosis do centromeres divide and the chromosomes move toward of their respective poles? answer: prophase 3)Which phase of mitosis is the last phase that

1) How much more energy is released in a 5.0 magnitude earthquake than a 4.0 magnitude earthquake. I know that each unit of Richter magnitude equates to roughly a 32-fold energy increase and that the amplitude has a tenfold increase but I am still confused

109. ## Chemistry

im not quite sure what to do with this problem... the info I have: -balanced equation= (CuCl2*2H20)=>CuCl2+2H2O -initial mass of copper compound: 0.94g Q: use stiochiometry to find the theoretical yield for the mass of copper (II) chloride we also used

110. ## Edit plz!

Communication skills happen to be one of the most important skills required in business. Because with this skills, I can explain my ideas, opinions, and also get feedbacks.

111. ## Manageral accounting

Cost Allocation prepare responses to the following questions in a Word document: • As financial managers, it is important that you identify and allocate costs appropriately. Discuss the major cost categories. What are some of the methods used to

112. ## Physics -- Repost

Homework Help Forum: Physics Posted by Sandra on Sunday, February 28, 2010 at 10:20am. Thank you for answering my previous questions! I have another one now in regards to the following question... An unknown potential difference exists between the inner

113. ## chem.

Silver(I) nitrate and sodium sulfate react to form silver(I) sulfate and sodium nitrate. Suppose 43.5 mL of 0.040 M silver(I) nitrate solution and 26.58 mL of 0.10 M sodium sulfate solution are mixed. What is the maximum number of grams of silver(I)

114. ## biology

1) What phase are daughter cells in as a result of mitosis? answer: Anaphase 2)During what phase of mitosis do centromeres divide and the chromosomes move toward of their respective poles? answer: prophase 3)Which phase of mitosis is the last phase that

115. ## English

Just have to write an essay and i was wondering if i can get any help to start writing my essay on who changed Siddhartha the most and why? Thank You(:

116. ## math

The ratio of w to x is 4:3, of y to z is 3:2, and of z to x is 1:6. What is the ratio of w to y?

117. ## Geometry

You have found an old parchment that describes the location of buried treasure! It states: "On Triangle Island there are only two trees, A and B, and the remains of a gallows. Start at the gallows and count the steps required to walk in a straight line to

118. ## intro to lan technologies

• Explain how you would create the users for the sales organization unit and how you can set up work groups in this particular situation. Keep in mind that you may have to name certain applications and allowable tasks for each individual or job role.

119. ## Chem

Why are the phase diagrams different for water and CO2?

120. ## CHEMISRTY

HOW MANY GRAMS OF MAGNESIUM ARE REQUIRED TO PRODUCE 2.154 GRAMS OF PRODUCT? STEP BY STEP EXPLAINATION

121. ## physics

A glass cleaner of mass 95 kg places a 22 kg ladder against the wall.The ladder is 10 m long and rests on a wet floor with a coefficient of static friction equal to 0.40. What is the maximum length that the window cleaner can climb before the ladder slips?

122. ## ALGEBRA

Examine the following equation: [z = 100 / (5t)]. What does “z” equal when: t = 2? t = 5? t = 20? t = 0?

write x^2-11/5 log(2 x-1)+11/5 log(x-2)+ c as a single log im not sure how to change the brackets

124. ## chem

If 0.120 moles of water are produced in the reaction H+(aq)+OH-(aq)-->H2O(l) delta H=-56.2 kJ/mol I have tried this problem a ton of times and aris keeps telling me I'm incorrect. Can you please help me with solving this problem

125. ## Geometry

How do you indicate congruent segments in a diagram?

126. ## chemistry

The reaction A + B to C + D is second order in A and zero order in B. The value of k is 1.10×10−2 M^{-1}\;min^{-1}. What is the rate of this reaction when A}]=0.124 M and B}]=3.89 M?

127. ## chemistry

For the reaction A to products}, the following data were obtained: t=0 s, A}]=0.715 M; 22 s, 0.605 M; 74 s, 0.345 M; 132 s, 0.055 M. What is the half-life of the reaction?

128. ## Science(Urgent)

1) How much more energy is released in a 5.0 magnitude earthquake than a 4.0 magnitude earthquake. I know that each unit of Richter magnitude equates to roughly a 32-fold energy increase and that the amplitude has a tenfold increase but I am still confused

129. ## Math

A submarine was cruising at a depth of 153 m. It then rose at 4.5 m/min for 15 min. What was the submarine's depth at the end of this rise? If the submarine continues to rise at the same rate, how much longer will it take to reach the surface?

130. ## Physics

We compare a silicon chip to a nerve membrane, with silicon having (about) twice the dielectric constant of the nerve membrane. Which of the following statements is true? A) 1cm^2 silicon chip has a higher capacitance than 1cm^2 nerve membrane. B) 1cm^2

131. ## math

When a lady faints, what number do you need to bring her?

132. ## English

* simple-- sim/ple The word is composed of two consonants. In the second syllable, there is no vowel. However, the second part is also a syllable. l is a syllabic consonant. What is syllabic consonant? Would you name the syllabic consonant? Thank you.

133. ## physics

A glass cleaner of mass 95 kg places a 22 kg ladder against the wall.The ladder is 10 m long and rests on a wet floor with a coefficient of static friction equal to 0.40. What is the maximum length that the window cleaner can climb before the ladder slips?

I need help with propose new hiring practices for the company to follow. In your proposal address the legal and ethical issues involved in discrimination and affirmativew action policies

135. ## Ethics

I have a paper started for my ethics class, but I am not sure if it fits the "criteria" or not. I am supposed to write about an ethic group to which I belong. I decided to do White women. But then I am supposed to have how the group colonized or immigrated

136. ## Bus210

write a 500-750 word paper in apa format describing the structure, business model, and culture of a beauty salon, provide justificationfor why you selected each element and explain how your choice may effect your business?

137. ## biology

What structure is produced when spindle fibers radiate from centrioles? Can you help please?

138. ## Chemistry

A 15.00 ml sample of a standard solution containing 1 g of CaCO3/L required 8.45 ml of EDTA to fully complex the Ca present. Calculate the volume of EDTA stoichiometrically equivalent to 1.0 mg of CaCO3.' Sorry, forgot to write the entire question.

139. ## English

Would doing a classification paper on skin types be to complicated?

the apothem of a square candle is 5cm,the side length is 10cm,the height is 9cm, what is its volume ?

141. ## algebra

Evaluate and tabulate the values of y for the given values of x. Tabulate your answer in the form of ordered pairs (x, y). y = 2x, for x = -2, -1, 0, 1, 2

142. ## English

Thank you for your last corrections. Can you check the grammar in the following sentences, please? 1) A: "What would you like to drink?" B: "I'll have a coke, please". A: "What about you?" (and not "And for you?")C: I'd like an orange juice. 2) The Celts

143. ## science

what way is bacteria and fungi important to the environment?

144. ## Chemistry

HI, we conducted a qualitative analysis, to identify the cations in an unknown sollution..trying to determine whether it had Al 3+, Fe (3), and Lead ions..i am having trouble understanding some parts of the procedure. before testing for aluminum and iron,

145. ## algebra

a. The sales representative here tells you they also have two floor plans available, but they only have 38 homes still for sale. Write an equation that illustrates the situation. Use x and y to denote floor plan one and floor plan two respectively

146. ## statistics

Please analyze the following data using the T-test for Unpaired data: A school district wants to determine if the girls are equal to boys in test scores. They took a random sample of 22 8th grade girls and 24 8th grade boys. The district looked at recent

147. ## english

please could someone tell whether the film miss congeniality was a book. If not can you think of a film that was a book, which had a character similar to gracie hart either as the fbi agent or as miss new jersey. many thanks

1) What phase are daughter cells in as a result of mitosis? answer: Anaphase 2)During what phase of mitosis do centromeres divide and the chromosomes move toward of their respective poles? answer: prophase 3)Which phase of mitosis is the last phase that

149. ## English

Just have to write an essay and i was wondering if i can get any help to start writing my essay on who changed Siddhartha the most and why? Thank You(:

150. ## Pre-Cal

1) Fill in the blanks As x --> pi^2, sin x --> ? and csc x --> ? I do not understand this!

151. ## Physics

How does the capacitance of a parallel plate capacitor change when its plates are moved to twice their initial distance and a slab of material with dielectric constant К = 2 is placed between the plates to replace air? I think that the capacitance would

152. ## chemistry

calculate the number of liters of liquid ethanol (density = 0.789g/ml) required to obtain a sample containing 1.00*10^25 C2H5OH molecules

153. ## Physics

h t t p : / / i m g 2 0 5 . i m a g e s h a c k . u s / i / c a p t u r e b b . j p g / i am stuck on part c how do i find work with out using the spring constant work equals force parallel times displacement at which the force is acted during... Work done

154. ## English

We are working on conjunctions. Rewrite this avoiding "also". If a pregnant mother smokes the child can be small. Also if the father smokes his spern can be abnormal. Also non-smokers have little risk of getting lung cancer. If a pregnant mother smokes,

155. ## calculus

You are given the following function. f(x)= (8+x)/(1-8x) (a) Find the derivative of the function using the definition of derivative. (b) Give the domain of the function. c) Give the domain of derivative of function?

156. ## Chemistry

Calculate the volume of EDTA stoichiometrically equivalent to 1.0 mg of CaCO3.'

157. ## macroeconomic

Which of the following items contribute(s) to an increase in real GDP? (i) The cost of cleanup after a hurricane hits Florida (ii) The market value of burglar alarms purchased to reduce crime (iii) The additional health care costs associated with smoking

158. ## calculus

find derivative of (8sqrt(x)+(9/2root3(x)))^2

159. ## ALGEBRA

Bill wants to open a business selling chairs. It will cost him a fixed amount of \$1,000,000 to open a factory, and a variable cost of \$5 to manufacture each chair. What will the total cost be to produce: 1,000 chairs? 100,000 chairs?

160. ## physics

Consider two small circular current loops. Suppose one loop is placed above the other (but not touching), with their areas oriented similarly. Do the loops repel, attract or have no effect when the currents are in the same direction? In the opposite

161. ## Algebra 1B

I really need help with this but I'm not sure if I'm going to put it in the correct form. The problem says to multiply and simplify by factoring. Assume that all expressions under radicals represents nonnegative numbers. Simplify your answers. Type in

162. ## Earth Science

Around what tectonic plate are most of the worlds volcanoes located. The Pacific plate. Is this correct?

163. ## statistics

Evolutionary theories often emphasize that humans have adapted to their physical environment. One such theory hypothesizes that people should spontaneously follow a 24-hour cycle of sleeping and waking—even if they are not exposed to the usual pattern of

164. ## Earth Science

How much more energy is released in a 5.0 magnitude earthquake than a 4.0 magnitude earthquake? I know that a tenfold increase in wave amplitude equals an increase of 1 on the scale so 1 to 2 = 10times so does that mean that 2 to 3 would be 10 more times?

165. ## Physics

At what distance from a carbon nucleus is the electric potential 1.8 V? Carbon atoms have 6 electrons in the atomic shell ...im very confused with this question, please help!

166. ## chemistry

HCl + Zn --> Predict the products and decide if it occurs. I have the activity series, but there's only H2 on there, not H.

167. ## chemistry

How many moles of a gas are in a container with a volume of 155 milliliters at a temperature of 35 degree celcus and a pressure of 1.1 atmoshheres? Please provide steps to get answer

168. ## Pre-Cal

1) verify the identity sec^2 (pi/2 - x) -1 = cot^2 x I think that we can replace sec with csc for the cofunction formulas since there is pi/2. Since there is squared and a 1 I think we could use one of the pythagorean identites but I am not sure which one.

Can you please prrof reread this paper for me? As you seen before I had to write about different ethnic groups and discrimination. Please let me know what you think. Thanks! Jews in America Jews in the United States have faced prejudice, segregation, and

170. ## science

what does monitoring information indicate about trends in amount of atmospheric carbon dioxide?

171. ## english/ Idoms

I need meaning of idoms . Do you know any web?

172. ## healthcare

I am having a hard time with the presentations. I don't know how to be creative with them.

173. ## English

What is the independent and dependent cluase of this sentence: "One of our most experienced trainers drowned in an incident with one of the killer whales," he said.

174. ## Psychology

Describe the major underlying assumptions of a biopsychological approach.

175. ## English

What is the meaning of 'guy'? Is it a boy or a man? Can we use 'guy' for a woman? If you say 'you guys' to some people, is it a little rude or an informal good expression? What connotation does 'guy' have?

176. ## English

Just have to write an essay and i was wondering if i can get any help to start writing my essay on who changed Siddhartha the most and why? Thank You(:

177. ## Precalculus

How do you find cos(sin ^-1 1.414/2)?

178. ## English

Just have to write an essay and i was wondering if i can get any help to start writing my essay on who changed Siddhartha the most and why? Thank You(:

179. ## Geometry

How do you indicate congruent angles in a diagram?

180. ## Pre-Cal

1) My last question was wrong. The question should read: Fill in the blanks As x --> pi+, sin x --> ? and csc x --> ? I do not understand this!

181. ## Math

4.905t^2 + 2.93t - 10 = 0 I have to solve for t. How do I solve this equation step by step? Thanks.

182. ## Calculus

A system of equations is given by: F1(x,y,a,b) = x² + bxy + y² - a – 2 = 0 F2(x,y,a,b) = x² + y ² - b² + 2a + 3 = 0 Where x and y are endogenous variables while a and b are exogenous variables. Compute the differentials δx/δb and δy/δa at the

183. ## Calculus

Find the partial derivative y with respect to s for the following function: y=[((x1)^2)+(x1)(x2)+((x2)^2)]/((x1)+(x2)) where x1=s+2 and x2=s^2+t^2+t . x1 means x subscript 1 x2 means x subscript 2

184. ## Algebra 2

How would I solve the equation: log(base2)4 - log(base2)(x+3) = log(base2)8 ? i think i have to start by doing 4/(x+3)=8

185. ## Science

If my project is about a lie detecting project waht would be my independent, dependent, and controlled variable?

How much more energy is released in a 5.0 magnitude earthquake than a 4.0 magnitude earthquake? I know that a tenfold increase in wave amplitude equals an increase of 1 on the scale so 1 to 2 = 10times so does that mean that 2 to 3 would be 10 more times?

187. ## English

1. Don is as strong as Bill. 2. Don is much stronger than Bill. 3. Don is a little stronger than Bill. 4. Don is somewhat stronger than Bill. 5. Don is less strong than Bill. 6. Don is much the best strongest of the three. 7. Don is the very best strongest

188. ## Math

Solve the system of linear equations by elimination. Thank You for your help. 8x+10y=3 3x-5y=2

189. ## English

What is the coordinating conjunctions that can be used to combine two complete sentences with a comma ?

190. ## calculus

Find an equation of the tangent line to the curve at the given point. y= (9x)/(x+1)^2 P = (0,0)

191. ## English

I Have No Idea What To Put For My Conclusion Of My Frankenstein Essay.... The Question For It Is Describe the significance of chapter five to the novel as a whole. Focus on the relevance and effect of the writer’s use of language to describe setting,

192. ## English

Make two clear sentences out of these five, avoiding 'so' and 'then'. The burglar climbed hastily out of the window. The burglar was terrified he'd be caught. The burglar didn't notice the water-butt. The burglar got stuck in the water-butt. The burglar

193. ## calculus plzz help!!!

Differentiate the following function. ((8x^1/2)+(9/2x^1/3))^2

194. ## Calculus

Find f '(a). f(x) = (x^2+1)/(x-6)

195. ## math

The wheel on a child's bicycle is 48 cm in diameter. To test the strength of the tire, William lifts the back wheel 1 m from the ground and spins it at 36 turns/min. He attached a blue sticker to the bottom of the tire beforehand. Assuming that William

196. ## MATH

3x=2y=4and 2y= ____________________________

197. ## algebra

I am still confused. y-4/y+2 = 1/6

198. ## Statistics

What key words tell you that the Hypothesis is to be set up as a 1 Tail UPPER?

199. ## English

Thank you very much for your last corrections! Can you check the grammar in the following sentences, please? 1) Antony uses his rhetoric to persuade people to mutiny against Brutus. 2) History was seen as a sort of moral teacher, where the Elizabethans

200. ## English

I forgot to include the following statements. 1) Use the simple past when reporting historical events and the simple present when referring to the main events in a plot. 2) The fact that Hamlet refers to himself using adjectives such as dullo

201. ## chemistry

You have a sample of magnesium chloride. If there are 3.90 mol of Cl, how many moles of magnesium atoms are there?

202. ## history

the American {third world counter offensive" from 1979-1989 did this policy improve the security and reputation of the United States?

203. ## help

1} Which of the items below is NOT a subcategory of change effected through similitude? a}emotional b}degeneration c}operational d}symbolic help plz...

204. ## Physics

What is the fundamental frequency for tube resonating in water if the speed of sound was 343.5 and the tube was 0.274 m out of the water.

205. ## English

Im working on prepostional phrases and need help with these problems: What is the prep. or prep. phrase and indicate whether it is an adj. or an adv? 1. An aid car raced through 3 red lights. 2. Latecomers may enter the theater only between acts.

206. ## Chemistry

(x)/(.00125-x)(.00000025-x)=Kc How do I solve for x or Kc?

207. ## math

what is a like fraction? greatest common factor? unlike fractions?

208. ## chemistry

when 50.0 ml of 2.00M KOH is reached with 50.0 ml of 2.00M HCl, the temperature rose from 20.0 degree celcus to 28.7 degree celcus. What is the heat generated by this neutralization? (Assume that the density fo the two 2 M solution is 2.00g/ml and that the

209. ## chemistry

What is the freezing point of a solution of 5grams of CaCO3 and 10ml of H20?

210. ## chemistry

If 4.57 grams of AgBr was isolated in a gravimetric analysis of a 9.30 gram sample, what is the % Br- by weight in the samples? please provide steps to get to answer

211. ## chemistry

A balloon has a volume of 2.75 liters at 25 degree celcus. What would the balloons volume be if the temperature is raised to 95 degree celcus and the pressure remains constant? please provide steps to get to answer

212. ## math

for ax^2 + bx + c with gradient 4x + 2 and a stationary value of 1 find a b and c and nature of point i think that its a minima and that its 2x^2 + 2x +2 but im not sure can someone check this please

213. ## algebra

Solve the following equation: k2 + 4k = 0 By factoring and By using the quadratic formula Can someone please help me to understand how to this problem...I do not understand the steps to get the correct answer. Thanks!!!

214. ## English

I forgot to include the following statements. Thank you a lot for your help. 1)Brutus fears what Caesar would become if he were elected king. 2) Brutus tries to convince the mob hat he was right in killing Caesar. 3)Political power is compared to an

215. ## Spanish

Can someone please proofread my spanish project? Hi I'm a second year spanish student and we just learned about past and imperfect tenses. I'm having a little trouble since my teacher refuses to look over projects and would greatly appreciate any feedback.

what is area

217. ## heathcare

what was champva year of establishment??

218. ## social studies

what is the purpose of the george washington cabeniet

219. ## english

i need help on finding the meaning of this quote "With the realization of one's own potential and self confidencne in one's ability, one can bulid a better world" thanks

220. ## Geography

please could someone help me answer these questions ...? globalisation brings many problems describe all the benefits in all the different stages of production and countries. globalisation brings many benefits describe all the benefits in all the different

221. ## English

In the novel Ceremony by Leslie Marmon Silko: Was Pinkie dependable?

222. ## english

what is autism? autism is a developmental disablity that affects a person's way of communicating with others, their social interaction, and educational performance. how i put this in diff words?

223. ## Math

X/((.00025-X)(.001-x)) how do i solve for x?

224. ## Phy

98N-T=10a T-18.89N=3a I worked on the problem and I end up getting two equations but now I have to find T and a. For some reason, I cant solve it. Thanks

225. ## geography

swimming is to butterfly as what is to dressage

226. ## Got It

problem solved

227. ## buissiness

i need help with why is Subway franchise a good investment? and the reasons have to be simple in bullet points PLZ i would appreciate ur help :)

228. ## MEDICAL TERMIONOLOGY

COULD ANYONE LET ME KNOW HOW TO COMPLETE APPENDIX E FOR HCA/220. I HAVE TO DEFINE THE WORDS I PART B AND C.

229. ## Chemistry

What is the boiling point of heaxane?

230. ## algerbra

4x^2/[(1.5-x)(2.0-2x)^2] = = 2.72 x 10^11 solve for x

231. ## XACC 280 (accounting)

Does anyone have a completed Appendix E- for Axia class XACC 280 Week 4 assignment - Preparing a financial statement worksheet? I am willing to pay for this if I can verify it was completed correctly.

ahexagon have the apothem of 6cm,the side length of6.93,and the height of 12cm. what is the volume?

233. ## math

I'm not sure how to divide rational expressions: ((1/x+1)+(1/x+2))/((1/x+2)+(1/(x+3)) -I got ((2x+3)(x^2+5x+6)/(2x+5)(x^2+3x+2) but it was wrong? Please help!

234. ## algebra

25f/2f-10 + 5f/10f-50

Around what tectonic plate are most of the worlds volcanoes located. The Pacific plate. Is this correct?

236. ## French

How would I pronounce seven thousand in French?

237. ## Physics

How does the conservation of mechanical energy explain why a planet in an elliptical orbit changes speed?

238. ## Pre-Cal

verify the identity sin x(1 - 2 cos^2 x + cos^4 x) = sin^5 x 1-2cos^2 x looks like 2cos^2x-1 its just backwards. I am not sure where to start.

239. ## college geomrtry

What are the differences between linear and quadratic equations? How are these differences displayed in a graph? Write a brief scenario that can be modeled with a linear equation. Summarize a situation modeled by a quadratic equation. Are there equations

240. ## Math

Logan changed bank account and now receives 1% more in interest than he used to. Write an expression?

241. ## Skill!

can u give me lists of skills required in busnisses! i got communication skills, teamwork skills, and i happen to need atleast 3 more...

4a+6=2a+12

243. ## math

Determine m given that m>0 and the points (m,3) and (1,m) lie on a line with slope m.

244. ## college

i need to know how to compose an essay

245. ## English

You forgot to check the grammar in the following sentences yesterday. Thank you. 1) You referred to question number 4 when answering question number 1. Your paragraph is off the subject (or you wandered off the subject?) 2) Express yourself in your own

246. ## bus!

why is patience important for business?

247. ## Physics

I'm really unsure of how to approach this question... Polystyrene has a very low dielectric constant compared to most other solid materials. Therefore, we predict for a polystyrene slab pushed between the plates of a parallel plate capacitor: a. that the

248. ## Physics

Hi, The resistance of each resistor in a series-parallel circuit was given and we measured the current and voltage across each resistor. Now, I have to find the theoretical values for I1, I2, etc. and V1, V2, V3, etc., using Kirchhoff's law and the known

249. ## english

i think that autistic people view this world better than ordinary ones. i think that they typically tend to see the world as one; everyone all linked together. is it true that they tend to see the world as one?

250. ## Physics

A bat flying in a cave sends out a sound wave to navigate. If the cave temperature is 10.8 C, and the sound the bats sends out takes 0.0679 s to echo back, how far away is the cave wall

251. ## English

Should the sentence say her and i or she and me? Next season we are determined to earn at least one place between[she,her]and[I,me].

252. ## English

Make two clear sentences out of these five, avoiding 'so' and 'then'. The burglar climbed hastily out of the window. The burglar was terrified he'd be caught. The burglar didn't notice the water-butt. The burglar got stuck in the water-butt. The burglar

253. ## College Physics

When I graphically find a vector sum and then analytically solve for the resultant, I am getting two completely different answers. Why might this be?

254. ## College Physics

What would be the direction of an angle at 50 degrees, 150 degrees and 295 degrees on the scale around the INSIDE of a force table?

what are elements of a literary ela ment chart

256. ## science

is aluminum MIXED with or COMBINED with other elements?

257. ## math214

In right triangle ABC, point O is the in center; CX 2”; AC 8”; AB 10; Find y.

258. ## algebra

Help! g/r+g - g/r-g

259. ## english

just wonderin-is there any sites on interent where i can find data bout autism 2010. i cant find anything anywhere

260. ## duratioon

how to calculate duration of a balance sheet

261. ## math

4x^2/[(1.5-x)(2.0-2x)^2] = = 2.72 x 10^11 solve for x

262. ## history

What place did the Israeli Olympic Team visit in the days prior to the hostage taking? I'm thinking it was a memorial of a concentration camp. I'm not too sure.

263. ## English

What is the prepostional phrase and indicate if it is adj or adv? 1) Mrs. Ruggiero loves to show pictures of her 5 grandchildren.

2t-1-3t+4

265. ## science

1.b) If this were a race, with the finish line at the staring line, what was his net displacement? This is a vector question since net displacement is a vector. Hence, was his net average velocity (which is a vector) zero over the duration of the race?

266. ## science

linear expansion

267. ## science

what is linear expansion

268. ## maths

what is 8% p.a on \$11000 over 3 years compounding anually

269. ## english

do people with autism look different from others or do they look normal like other normal people?

270. ## english

All their focus appears to go towards somewhat way beyond imagination. -atutistic people-make sense?

271. ## History

why were the munich olympic games viewed as being of particular importance world politics, national relations, and reconciliation with the Jewish people? I think the Holocaust occured before that and Germany wanted to prove that they were moving forward

272. ## physical

What is pressure point?

273. ## college

how to I figure how much copper is in 2.154 gram of copper sulfide?

274. ## calculus

Differentiate the following function. (7x-5)(3x+9)

275. ## History

What had occurred 40 years prior to the Munich Olympics which made the games so important? The only things I got are the Holocaust, the separation of Israel and Palestine and WW2. Is there anything else that was major?

276. ## college

how many grams of magnesium are required to produce 2.154 g of magnesium nitride?

277. ## SCIENCE

is aluminum MIXED with or COMBINED with other elements?

2t-1-3t+4

279. ## math

what is square roots

280. ## math

what is a surfex angle

281. ## English

When I write a classification can i put more than one subject in a paragraph or dose each subject needs it own paragraph

282. ## math

6 6 6 6 = 5 fill in the expressions to make this equation true

283. ## college

how to figure out how many grams of magnesium are required to produce 2.154grams of product?

284. ## SCIENCE

should i say: red in color OR reddish in color

relationship between the total ounces of water collected,w, and the number of 4-ounce samples,s