1. Chemistry

Predict how the entropy of the substance is affected in the following processes: a) O2 (g,200 kPa, 300k) --> O2 (g, 100, 300k) b)Br2 (l, 1 bar, 25 degree C) --> Br2 (g, 1 bar, 25 degree C) C)Fe (s, 1 bar, 250 degree C)--> Fe(s, 1 bar, 25 degree C) will

2. Chemistry

Calculate ΔG° for the following reaction at 298 K.? A+B --> 2D ΔH° = 775.0 kJ ΔS°=296.0 J/K C --> D ΔH° = 446.0 kJ ΔS°=-218.0 J/K A+B --> 2C ΔG° = ? kJ I know I am suppose to reverse the (C --> D) and add a coefficient of 2 to both the enthalpy

3. Chemistry

If delta H°rxn and delta S°rxn are both positive values, what drives the spontaneous reaction and in what direction at standard conditions? The spontaneous reaction is a)enthalpy driven to the left. b)entropy driven to the right. c)entropy driven to the

4. chemistry

Where possible, classify these systems as reactant-favored or product-favored at 298 K. If the direction cannot be determined from the information given, classify the reaction as "Insufficient information". a)2A(g) + 3B(g) -->4C(g) delta H = -95kJ b)2A(g)

5. chemistry

What are the products of the reaction between nitrous acid and strontium hydroxide?

6. math

1. Solve: 6C3 120***? 720 20 240 is this right?

7. math (cant figure it out)

Activity Boys Girls Total Walk 3 6 Bike 5 3 Skateboard 2 1 Total ______________ What percentage of the total students chose skateboarding? 10% 20% 30% none of these** . 4. What percentage of the boys chose walking? 30%* 45% 25% none of these . 5. What

8. Probability

Let U, V, and W be independent standard normal random variables (that is, independent normal random variables, each with mean 0 and variance 1), and let X=3U+4V and Y=U+W. Give a numerical answer for each part below. You may want to refer to the standard

all 500 students at robinson junior high were surveryed to find their favorite sport how many more students played football than basketball? Soccer: 10%, Football:38%, basketball: 27%, Baseball: 25%. . . . A.325 students B.135 students C.190***** D.55

Which of the following types of information is NOT suited for display on a scatter plot? 1. relationship between age and number of books read in a year*** 2. relationship between height and shoe size 3. relationship between calories consumed and body

11. Maths

The owner of a music store received a shipment of 1,532 cds the CDs came in 37 boxes the same number of cds were in 36 of the boxes how many cds were in the remaining box

12. Chemistry

Assuming that the specific heat of the solution is 4.18 J/(g⋅∘C) and that the calorimeter itself absorbs a negligible amount of heat, calculate ΔH in kilojoules for the reaction CaO(s)+H2O(l)→Ca(OH)2(aq) When 1.045 g of CaO is added to 50.0 mL of

13. statistics

The Acme Candy Company claims that 60% of the jawbreakers it produces weigh more than .4ounces. Suppose that 800 jawbreakers are selected at random from the production lines. Would it be unusual for this sample of 800 to contain 494 jawbreakers that weigh

14. physics

When heat transfers into a system, is the energy stored as heat? Explain briefly.

15. Physics

A man pulls a rope attached to a crate with a force of 120 N. If the rope makes an angle of 130 degrees with the ground, find the components of the force.

16. chemistry Equations

Write euations to show how a buffer made up of equimolar amounts of acetic acid, CH3COOH, and acetate, CH3COO-, would behave when (a) HCl was added and (b) NaOH was added. Is this right,If not what is the correct way? CH3COOH + HCl ----> CH3COOHCl + OH

17. chemistry urgent

NH4NO3(s)+H2O(l)→NH4NO3(aq) ΔH = +25.7 kJ. What is the final temperature in a squeezed cold pack that contains 45.5g of NH4NO3 dissolved in 125 mL of water? Assume a specific heat of 4.18J/(g⋅∘C) for the solution, an initial temperature of 29.0∘C,

18. Probability

Let Θ be an unknown random variable that we wish to estimate. It has a prior distribution with mean 1 and variance 2. Let W be a noise term, another unknown random variable with mean 3 and variance 5. Assume that Θ and W are independent. We have two

19. chemistry

If 2.33 L of propane (C3H8) at 24oC and 67.2 kPa is completely burned in excess oxygen, how many moles of carbon dioxide will be produced? a. Write a balanced equation for the reaction. b. Use stoichiometry to find the volume of carbon dioxide. c. Use the

20. Statistics

Recently, a university surveyed recent graduates of the English Department for their starting salaries. Four hundred graduates returned the survey. The average salary was $25,577. The population standard deviation is$2,566. What is the 95% confidence

21. Ollu

On a steamy mirror wipe away just enough to see your full face. How tall will the wiped are be compared with the vertical dimension of your face?

22. SS

What might happen in Cyprus in the future, politically and economically?

23. math

8.Mary invested RM3000 in two accounts, some at 12% per annum and the rest at 8 percent per annum.Her total interest for one year was RM3200.how much was invested at each rate? 9.RM 1999 was invested for a certain period. The simple interest earned was

24. physics

A 150-g block on the end of a spring with a spring constant of 35 N/m is pulled aside 25 cm and released from rest. In the electrical analog the maximum charge on the capacitor is 0.25 C.The maximum current in the LC circuit is

25. math

A sum of money,X was deposited in a saving account at 10 percent compounded daily on 25 july 1993. on 13 august 1993, rm600 was withdrawn and the balance as on 31 december 1993 was RM 8900.calculate the value of X using exact time and 360 day year.

26. Chemistry

A student intend to prepare 200ml of 0.3M NaCl solution . The mass in gram of NaCl needed to prepare solution is ?!

27. Chemistry

Calculate ΔH∘f (in kilojoules per mole) for benzene, C6H6, from the following data: 2C6H6(l)+15O2(g)→12CO2(g)+6H2O(l) ΔH∘ = -6534kJ ΔH∘f (CO2) = -393.5kJ/mol ΔH∘f (H2O) = - 285.8kJ/mol

28. Chemistry

The equilibrium constant is 16 for the gas phase reaction SO2 + NO2 SO3 + NO at a certain temperature. If 3.0 moles each of SO2 and NO2 are placed together in an empty 1.0 liter flask and the system is allowed to come to equilibrium at this temperature,

29. Statistics

Mileage tests were conducted on a randomly selected sample of 100 newly developed automobile tires. The results showed that the average tread life was 52,515 miles with a standard deviation of 3,550 miles. What is the best estimate of the average tread

30. Chemistry

Given the equilibrium reaction N2(g) + 3 H2(g) 2NH3(g) + heat, an increase in temperature will: a) Increase the value of K b) Decrease the value of K c) Increase or decrease the value of K depending upon the concentration of reactants d) Will have no

31. Statistics

On an exam on probability concepts, Sue had an answer of 13/8 for one problem. Explain how she knew that this result was incorrect.

32. Chemistry

In the. Reaction (Na2co3+CaCl2-->2NaCl+caco3) The precipitate is :

33. Probability

Consider a fire alarm that senses the environment constantly to figure out if there is smoke in the air and hence to conclude whether there is a fire or not. Consider a simple model for this phenomenon. Let Θ be the unknown true state of the environment:

34. statistics

Fill in the blanks with the appropriate raw scores, z-scores, T-scores, and percentile ranks. NOTE: the Mean = 50, SD = 5. ________________________________________ Raw z T %ile ________________________________________ 35 1.2 35 16

35. math

RM65000 will be invested for 6 years 9 months. if the investment will be offered 5% compounded semi annualy for the first 2 years, 6% compounded monthly for the next 18 months and 7% compounded daily for the rest of the period ,find the future value of

36. Probability

Let N,X1,Y1,X2,Y2,… be independent random variables. The random variable N takes positive integer values and has mean a and variance r. The random variables Xi are independent and identically distributed with mean b and variance s, and the random

37. Statistics

A survey of an urban university (population of 25,450) showed that 878 of 1,119 students sampled supported a fee increase to fund improvements to the student recreation center. Using the 95% level of confidence, what is the confidence interval for the

38. chemistry

Lactic acid (CHgCHOHCOgH) is found in sour milk, in sauerkraut, and in muscles after activity. (K, for lactic acid I 1.4 X 1074.) (a) If 2.75 g of NaCH3CHOHCO2,

39. Probability

Let X be a random variable that takes non-zero values in [1,∞), with a PDF of the form fX(x)=⎧⎩⎨cx3 if x≥1, 0,otherwise. Let U be a uniform random variable on [0,2]. Assume that X and U are independent. What is the value of the constant c? c=

40. statistics

A sociologist is interested in the relation between x = numberof job changes and y = annual salary (in thousands of dollars) forpeople living in the Nashville area. A random sample of 10people employed in Nashville provided the followinginformation: x

41. math (SIMPLE INTEREST)

4.the amount in an account which was opened 180 days ago is RM205. iF the account was offered a simple interest of 5 percent per annum, find the original principal. 5.how long does it take a sum of money to double itself in four years ?

A 20.0 L reaction vessel contains 0.016 moles CO2, 1.05 moles of CO, and 2.00 moles of C. The mixture is approaching the following equilibrium: CO2(g) + C(s) 2CO(g) a) Calculate the reaction quotient Q. b) If value of K is 1.17, predict which direction the

43. Physics

I've been working on this problem for close to an hour now and keep getting very wrong numbers... The two objects with different mass (m1 = 5.0 kg and m2 = 3.0 kg) in the Atwood's machine shown in the figure are released from rest, with one object at a

1. If a bat emits 10 sounds in 5 seconds, what is the frequency of the bat's vocal outbursts (rounded to first decimal place) My answer: 2.0 Hz 2.If one crest has a 3 cm amplitude and interacts with another pulse to produce a crest 8 cm high this

45. Chemistry

A student mixed 40ml of 0.2m Na2co3 solution with 50 ml f 0.25M cacl2 solution , what is the except number of moles of naclkkw that I will be formed ?

46. Chemistry

If 2.5 g of NaOH is dissolved in 253 mL of water, what is the pH of the solution?

Concision Rewrite the sentences using concision techniques (replacing phrases with words, combining sentences, etc.) discussed in class to simply these wordy sentences. 1. Critics cannot avoid employing complex and abstract technical terms if they are to

48. math

miss Thao owns a small hotel with 30 identical rooms. she finds that if she charges a price of 12 dollars ( or less) per room per day, all the rooms are rented. for every 1 dollar in price, 2 rooms remain vacant. each day, maintenance cost 4 dollars per

49. Math

Explain a real-world problem that you used math to solve. What mathematical expressions did you use in your problem solving? Define your variables and explain your expression. My real-world situation would be making a cake and converting the cups into oz.

50. French

travaille dans un magasin. ( rewrite the article and the noun) The salesclerk

51. Macroeconomics

A company is producing 100 units. At this quanity, it's average total cost is $25, and it's total fixed cost is$2,000. How much is it's total variable cost?

52. COM 200

All of the following are accurate tips for effective listening EXCEPT: (Points : 1) Listen to what the speaker doesn’t say as much as you listen to what is said. Paraphrase what you understand the speaker’s message is to help ensure understanding.

53. Physics

Table 1: Temperature and volume data Trial Temperature (Celsius) Volume (mL) Starting Volume Room Temperature = Hot Water Trial 1 106 5.2ml Hot Water Trial 2 107 5.4ml Cold Water Trial 1 lo 4.3ml Cold Water Trial 2 lo 4.3ml PLOT AREA (Insert a graph that

54. Probability

Manhole explosions (usually caused by gas leaks and sparks) are on the rise in your city. On any given day, the manhole cover near your house explodes with some unknown probability, which is the same across all days. We model this unknown probability of

55. math

what sum of money will become RM15000 in three year at a simple interest rate of 8% per annum?

56. Bio/Chem

If i change the concentration of the 3% hydrogen peroxide solution to 1.5%, am I changing its concentration or percent concentration?

57. Bio

Scientific name for cow liver (used for a bio lab)

58. information literacy

For an article to be considered scholarly, what element must it include? A: Detailed diagrams of the concepts presented B:criticism by academic peers C:a bibliography or a list or work sited D:a complete biography of the author or authors

59. Math

I studied for four hours. I added 2 more hours every day for a week. How many more days do I have to study until I have spend 20 hours studying?

60. math

how many ways can 10 runners finish a race. 10 could finish 10 9 could finish 9 and so on would I times 10*9*8 ect that number seems way to big.

61. Math

Mrs Chan has twice as many $5 notes as$10 notes and twice as many $10 notes as$50 notes. She has a total of $1080. How many$10 notes does she have?

62. Social Studies

Which of the following facts could be best used when supporting Kurdish independence? A. Most of the Kurdish people are not Shia Muslims, but are Sunni Muslims. B. Outside governments have repressed Kurds harshly before. C. Kurds were included in Iraq by

63. Economics

Please provide a definition of "Allocative Mechanism."

64. L.O

identify and introduce the human rights violation

65. social studies

How did the Fugitive Slave Act and the Kansas-Nebraska Act further divide the North and South? What role did the concept of popular sovereignty play in these conflicts? Do you think there was any way to avoid the violence that came out of this era? pls

66. chemistry

Calculate the enthalpy change, ÄH DeltaH, for the process in which 12.7g g of water is converted from liquid at 7.3 ∘ C \, ^\circ C to vapor at 25.0 ∘ C \, ^\circ C . For water, ÄH vap \Delta H_{\rm vap} = 44.0kJ/mol kJ/mol at 25.0 ∘ C \, ^\circ C

67. SS

How does Iran spend its money?

68. math/geometry

Oil from a drum leaks into water surrounding the drum, creating a circular oil slick 100 square feet in area.Find the scale factor of the size transformation of the oil slick when it is 450 square feet in area. Round to the nearest hundredth.Where is the

69. physics

a bus decreases its speed from 80kmh-1to 60kmh-1 in 5 sec find the acceleration

70. Psychological and Psychophysiological Stress Disor

What kind of traumatic events cause undiagnosable psychological disorders?

71. Trig Maths

solve the equation 5sin(θ -pi/6)=8cosθ for values of 0

72. Chemistry

1.2g of NaCl as used to prepare 200 ml solution , what is the molar concentration of NaCl in solution ?

73. Physics

A 60 man choir sings with the sound intensity of 70 dB in a 12m distance from the choir. a) What is the average sound intensity in this distance? b) What is the sound intensity in a 20 m distance ? Help please :)

74. Math

Write an algebraic expression for "15 less than the product of the square of x and 5."

75. math

amy is 5 feet tall shes standing 12 feet from a street light if amy's shawdow is 4 feet long which porportion could be used to find the height of the street light

76. chemistry

HCL acid is available as a stock solution with a concentration of 10 mol/L. If you need (2.100*10^0) L of (2.3*10^0) mol/L hydrochloric acid, approximately how much distilled water will you need to make the dilution?

77. Physics waves

I am stuck with both of these questions. Thanks in advanced! 1. If one tone has a frequency of 110 Hz and another tone is played near it with a tone of 113 Hz, the beat frequency is ___ Hz 2. A standing wave has 3 nodes in a string 20 m long. The

78. Maths

Fred is 10 yrs older than Ted. In 3 yrs time Fred will be 3 times as old as Ted. Let Fred be x yrs old now. Write an equation to represent this situation. Solve equation and state how old each person is now.

79. physics

Find the distance on a flat screen between the principal image and the second order bright fringe for red light(wavelength=664nm)if there are 900 slits per centimeter and the screen is 2.75 meters from the slits.

i need help on a few questions from the book October sky/rocket boys so here they are: -name of the rockets (through chapters 1-8) and why did they name them that ? -what does sonny name his new launching site -who is valentine -why is the football team so

Cohesion and Coherency/Sentence Variety This short paragraph has two distinct problems. First, to improve cohesion, rewrite these sentences so that old information is at the beginning of each sentence. Second, combine sentences and/or provide transitions

82. us history

Can you check if my answers are correct? When Jewish leaders proclaimed the independent state of Israel in 1948, the USA A. refused to recognize it until democratic elections were held B. broke diplomatic relations with most Arab states C. recognized the

83. US history

Can you check if my answers are correct? Martin Luther King, Jr.’s eloquence hid the fact of his lack of formal education beyond the eighth grade. is it true? When black students tried to enter Little Rock’s Central High School in 1957, the governor

84. statistics

3coins are tossed calculate the followin probabilities p(3heads) p(2heads and 1 tail) p(3 tails)

85. Chemistry

If the equilibrium constant for a reaction A + B C + D is K, which is true of the equilibrium constant K* for the reaction C + D A + B under the same conditions? A) K* = K B) K* = 1/K C) K* = 1 - K D) K* = 1 - (1/K) E) K* = 1 + K

86. math

4 red,5 blue,1 yellow marble Find the probability of picking a red marble then not replacing it and then drawing a blue marble. answer as a fraction,decimal and percent.

87. Maths, biology, accounting, business economics

What career could one study with these subjects

88. math

Question 12.12. Katie had an unpaid balance of $1,734.50 on her credit card statement at the beginning of January. She made a payment of$165.00 during the month. If the interest rate on Katie's credit card was 7% per month on the unpaid balance, find the

89. math

Right triangle DEF has sides that measure x, x, and x squared for the some value of x. What is the area of triangle DEF to the nearest 0.1 square unit?

90. Chemistry

In an experiment we have 4 liters of AlAin water in contain or A , and 2 liters of dubai water in contain out B . The alkalinity of water in container A and the alkalinity of water in container B are 50 and 150mg/l as caco3 ,,respectively the alkalinity of

91. Chemistry

The separate suspended solid from a solution , we may use .......

92. Chemistry

The measured experimental volume of ascetic acid in a sample of vinegar was 7% and the manufacture claimed volume is 5.8% , what is the percentage error ?

93. Penn Foster

Dramatic irony means that

94. Chemistry

The mass of watch glass is 24.5 g , the mass of watch glass plus white crystals befor drying is 29.1g , and the mass of watch glass and white crystals after drying 27.9 , thus the mass of the white crystals is !????!

95. Chemistry

What is the molarity of a solution of H3PO4 if 11.1 mL is neutralized by 33.2 mL of 0.161 M NaOH?

96. Dynamics

A particle of mass m starts from rest and slides on a polished track around a vertical circular loop of radius a as shown. Show that the minimum starting height h above the bottom of the loop in order that the particle will leave the track at any point is

97. Chemistry

22mL of hydrogen was collected over wter at 19C and 745mmHg. What mass of magnesium is reacted (1:1 mole ratio)

98. algebra

perform the given operation. Let U = {1,2,3,4,5,6,7,8,9,10} enter the answer {1,2,8} U 2,8,9}

99. calculus

u have 7 different pass codes from a choice of 8 numbers how many possible outcomes are there

100. Math

A model plane flies 18 ft per 2 seconds. What is the planes speed in miles per hour? Round to the nearest tenth.

101. algebra

Let U = {4,5,6,7,8,9,10}, A = {4,5,6,7}, B = {4,5,8,9} and C = {6,8,10}

102. algebra

How do you factor 2a^2+5x+3

103. Math

For f(x)=3x+2. Find f(4)

104. Math

Write an equation in slope intercept form of the line that is perpendicular to the given line and that passes through the given point 3x-4y=8 ; (-6,5)

105. Algebra 1

How do u graph inequalities?!?

106. chemistry

HCL acid is available as a stock solution with a concentration of 10 mol/L. If you need (9.0*10^-1) L of (2.50*10^0) mol/L hydrochloric acid, approximately how much distilled water will you need to make the dilution?

107. physics

A square room has 3 mirrored walls of length L with one side missing. A laser is fired from the center of the open side of the room with an angle of incidence, I, toward the wall on the right. If the reflected beam is to hit a target on the back wall .80

108. math

3/4 of a gallon is 6/7 of the amount originally in the container. how much was in container originally

109. math

find x when g(X)=0

110. Physical sciences

The ruler now make contact with the neutral sphere.what happens to electrons?

111. statistics

discuss the contribution of computer in the development of science and technology

112. statistics

data shows number of absent student of statistic ciass. 3,5,7,4,6,0,1,4,3,2,8,5,4,7,1,5,2,6,7,8,3,9,1,0,5,6, form a frequency distribution by taking one class interval.

|3x+1|-|2-x|

114. physics

If a boulder of 9.7 tons is placed on a 70 degree incline, how much extra force would be needed to push the boulder up if the incline increases up by 5 degrees?

P(-1.86

116. Chemistry

In TDS experiment , the mass of the empty beaker was 25.683g , and the mass of the beaker after water evaporated 25.687 g , if the volume of the sample 50 ml , then the TDS of the water sample is ?

117. Trig Maths

solve the equation 5sin(θ -pi/6)=8cosθ for values of 0

118. Chemistry

What are the Salts are taken into consideration in the calculation of the total alkalinity ????

119. English

1. I have seen her once. 2. I have once seen her. 3. I once have seen her. Which one is correct?

120. Chemistry

If we put a drop of acid in a cup of natural water , the PH will ?

121. Chemistry

A water sample has TDS of 6000mg/l and the total hardness f 60mg/l , the water can be classified as ........

122. Chemistry

What is the molarity of a NaOH solution if 21.3 mL of the NaOH solution is neutralized by 10.4 mL of 6.10 M H3PO4?

123. Chemistry

To remove temporary hardness we may use ?!!!