# Holly

Most popular questions and responses by Holly
1. ## chemistry

A sample of O2 gas is collected over water at 23C at a barometric pressure of 751 mmHg (vapor pressure of water at 23C is 21 mmHg). The partial pressure of O2 gas in the sample collected is: (a) 21 mmHg (b) 751 mm Hg (c) 0.96 atm; or (d) 1.02 atm The

2. ## Chemistry

Barium carbonate and nitric acid reacts in a double displacement reaction. One of products also dissociates and evolves carbon dioxide. Write the net ionic reaction including the proper use of phase labels for this solution run in aqueous solution. After

3. ## Math

1. Which property is NOT a characteristic of a parallelogram? A. Opposite sides are not congruent B. All angles are congruent** C. Opposite sides are parallel D. Opposite angles are congruent

4. ## Chem 101

In a fission reaction, uranium-235 bombarded with a neutron produces strontium-94, another small nucleus, and 3 neutrons. Write the nuclear equation for this reaction.

5. ## calculus

Find the points on the curve below at which the tangent is horizontal. Use n as an arbitrary integer. (Enter your answers as a comma-separated list.) y = sin x/ 2 + cos x

6. ## Chemistry

Identify the salt that is produced from the acid-base neutralization reaction be- tween sodium hydroxide and hydrocyanic acid (HCN). 1. sodium cyanide 2. sodium acetate 3. sodium amide 4. sodium formate

7. ## social studies

1.Which is an effect of deforestation? A. soil erosion B. air pollution C. water pollution------- D. earthquakes 2. Which of the following is a reason so many people have migrated from Middle America to other regions? A. They dislike the region's climate.

8. ## Math

Outside temperature over a day can be modelled as a sinusoidal function. Suppose you know the high temperature for the day is 87 degrees and the low temperature of 63 degrees occurs at 5 AM. Assuming t is the number of hours since midnight, find an

A 80- kg child sits in a swing suspended with 2.6- m-long ropes. The swing is held aside so that the ropes make an angle of 46 o with the vertical. Use conservation of energy to determine the speed the child will have at the bottom of the arc when she is

10. ## Social Studies

Where can I find a map that shows Columbus' voyage from Spain to the West Indies?

11. ## Physical Science

How do you write the chemical equation for neutralization of nitric acid, HNO3, with magnesium hydroxide, Mg (OH)2, first with spectator ions and then without spectator ions?

12. ## Chemistry

A solution contains 25 mmol of H3PO4 and 10. mmol of NaH2PO4. What volume of 2.0 M NaOH must be added to reach the second equivalence point of the titration of the H3PO4 with NaOH?

13. ## chemistry

2.The data in the table show the amount of a 500 g sample of sodium-24 over time. Make a graph of the data (remember to label all axes and title the graph). What is the half-life of sodium-24? Explain how you determined your answer. Sodium-24 decays by

14. ## Pre-calculus help

I have two problems I am stuck on, if you could show me how to solve the problems it would be much appreciated. 1) Find sin 2x, cos 2x, and tan 2x from the given information. tan x = − 1/6, cos x > 0 sin 2x = cos 2x = tan 2x = 2) Find sin 2x, cos 2x, and

15. ## chemistry

Describe what happens in a fission reaction. What is a commonly used isotope in a nuclear fission reactor? Describe how a fission nuclear reactor power plant works.

16. ## Physics

A mechanic uses a chain and block to lift a 875-kg engine 4.00 m to the top of the garage. The downward force in the chain over the 4.00 m distance is 5.00 x 10^4 N. A) Calculate the work done in raising the motor B) How much useful work was done? C) What

17. ## Chemistry

What is the molarity of an HNO3 solution if 24.1mL of a 0.250M Ba(OH)2 solution is needed to titrate a 15.0mL sample of the acid? Can you tell me the process to finding this answer?

18. ## Chemistry

What is the oxidation number for each atom in NH4F? N=+3, H=-4, F=+1 N=-3, H=+1, F=-1*** N=+3, H+1, F=-1 N=-3, H=-1, F=+1

19. ## accounting

P20-2A For the year ended December 31, 2010, the job cost sheets of DeVoe Company contained the following data. Job Number Explanation Direct Materials Direct Labor Manufacturing Overhead Total Costs 7640 Balance 1/1 $25,000$24,000 $28,800$77,800 Current

20. ## Physics

A farmer drives a 0.100 kg iron spike with a 2.00 kg sledge hammer. The sledge hammer moves at a constant speed of 3.99 m/s until it comes to rest on the spike after each swing. Assuming all the energy is absorbed by the nail, and ignoring the work done by

21. ## physics

a bird flies 3km west and then 4km south. find the resultant displacement of the bird

22. ## astronomy

Earth is spinning at 1670 km/h at the equator. Use this number to find Earth’s equatorial diameter.

23. ## Math

Please help. 51. Solve: 125=(x3)/0.3^-3 a.7 b.14 c.15 d.9 53. 49x-2 = 7Ö 7 a.-5/4 b.5/4 c.11/4 d.-11/4 60. Simplify: 2log^3 6 - log^3 4 a.3 b.6 c.4 d.2 61. Solve the equation: logb (x^2 + 7) = 2/3logb 64 a.9 b.3 c. √23 d. ±3 62. Solve: (The fifth root

24. ## Chemistry

List the amino acid side chains that can accept H+ and those that can donate H+ during enzyme catalyzed reactions. I have lysine, arginine, and histidine as acceptors and serine, threonine, and tyrosine as donators. Could someone just tell me if those are

25. ## physics

A box weighing 890N is pulled along a horizontal surface by means of a string which is at 30o above the horizontal. If the coefficient of kinetic friction is 0.2 and the box is accelerated at 0.8 m/s2, what is the tension in the string

26. ## Chemistry

How much heat would be required to convert 234.3 g of solid benzene, C6H6(s), at 5.5 c into benzene vapor, C6H6, at 100 c? mp of C6H6=5.5c bp of C6H6=80.1 c mhc C6H6(l)=136J/mol*c mhc C6H6(g)=81.6J/mol*c mhfusion at 5.5 c=9.92kJ/mol mhvaporization at 80.1

27. ## chemistry

If 10g of steam at 110 c is pumped into an insulated vessel containing 100g of water at 20 c, what will be the equilibrium temperature of the mixture? spheat H2O(l)=4.18J/g*c, spheat h2O(g)=2.03J/g*c, heat of vap H2O(l)=2.260kJ/g

28. ## statistics

Please let me know if I solved this right The lifetime of television produced by the Hishobi Company are normally distributed with a mean of 75 months and a standard deviation of 8 months. If the manufacturer wants to have to replace only 1% of its

29. ## statistics

A study of 35 professors showed that the average time they spent creating test questions was 13.5 minutes per question. The standard deviation of the population is 3.8. Which of the following is the 99% confidence interval for the average number of minutes

30. ## math

which expression is equivalent to 4*4*4*4*4*4*4*4? Debra has 2/3 of a pound of loose green tea leaves. If she wants to keep one-half of the tea at home and the other half at work, what fraction of a pound will she have at work? 7-5/7= what is (-7) to the

31. ## Physics

A car sits in an entrance ramp to a freeway, waiting for a break in the traffic. The driver sees a small gap between a van and an 18-wheel truck and accelerates with constant acceleration along the ramp and onto the freeway. The car starts from rest, moves

32. ## Science

A sled and rider with a combined weight of 59 kg are at rest on the top of a hill 24 m high. (a) What is their total energy at the top of the hill? (b) Assuming there is no friction, what would the total energy be on sliding halfway down the hill?

33. ## Art

1. Which of the following answer choices contains a metaphor? A. His skin was sandpaper** B. The sun sparkled like a diamond C. She wanted to be like the birds and fly away D. They felt free when they ran across the doors 2. What is a key characteristic of

34. ## programming

how do you design a program that asks the user to enter a store's sales for each day of the week. the amount should be stored in an array. use a loop to calculate the total sales for the week and display the result.

35. ## Calc problem

Consider the function y=(kx)/(x-k) a. Show that y is symmetric with respect to the line y=x. b. Write the equations of the horizontal and vertical asymptotes of y. c. Find the point(s) of intersection of y with the line x-y=-2k, and find the slope of the

36. ## Public Speaking

Evaluating audience feedback to your speech presentation usually happens: A. before the speech. B. after the speech. C. during the speech. D. in the speech preparation

37. ## maths

a cube haas a volume of 27cm3 what is the length of one side of the cube

38. ## chemistry

Calculate the pH at the point in the titration of 25.00 mL 0.108 M HNO2 at which 10.00 mL 0.162 M NaOH have been added. For HNO2, Ka=5.1 x 10^-4 and: HNO2 + OH- -----> H2O + NO2- I know that HNO2 is a weak acid and that 5.1 x 10^-4=[NO2-]/[HNO2][OH-]. NaOH

39. ## math

There are 6 pizzas for 8 people. If the pizzas are divided equally, how much pizza will each person receive?

40. ## trig is killing me...

the angles of elevation of a tower at two places due west of it are 63 degrees and 56 degrees. given that the foot of the tower and the two points are on ground level and the distance between the two points is 20 meters, find the height of the tower. You

41. ## algebra

A gym has an enrollment fee of $80 and a$25 fee per month of membership. Write an expression to represent the total cost of m months of membership?

42. ## chemistry

Calculate the pH at the point in the titration of 25.00 mL 0.108 M HNO2 at which 10.00 mL 0.162 M NaOH have been added. For HNO2, Ka=5.1 x 10^-4 and: HNO2 + OH- -----> H2O + NO2- I know that HNO2 is a weak acid and NaOH is a strong base. Help given to me

43. ## words

what is a huge limestone mass on Spain's southern coast? it starts with...rock _ _ _ _ _ _ _ _ _ _ _ help plz!!! Rock of Gibraltar. http://www.andalucia.com/gibraltar/home.htm

44. ## chemistry

An equilibrium mixture of SO2,SO3 and O2 gases is maintained in a 11.5 L flask at a temp at which Kc=55.2 for the rxn: 2SO2 + O2 2SO3. If the # of moles of SO2 and SO3 are =, how many moles of O2 are present? I let SO2 and SO3 =x and O2=y. Since SO2 and

45. ## chemistry

Which represents the largest pressure? A)five mmHg B)one atmosphere C)one millimeter of mercury D)one hundred pascals E)five pounds per square inch I tried converting them all to mmHg and I think the answer is B, but I just want to make sure.

46. ## Math

A cookie jar contains 3 chocolate-chip, 2 peanut butter, 1 lemon, 1 almond, and 5 raisin cookies. a) In how many ways can you select some cookies, if you must include at least one chocolate-chip cookie. Please please please.. reply back asap.. i am totally

47. ## Physics HELP!

A war-wolf, or trebuchet, is a device used during the Middle Ages to throw rocks at castles and now sometimes used to fling pumpkins and pianos. A simple trebuchet is shown in the figure. Model it as a stiff rod of negligible mass 3.00 m long and joining

48. ## Maths

Sarah said when x=3 then the value of 4x squared is 144 holly said when x=3 then the value of 4x squared is 36 who is right and why?

49. ## Chemistry

What are transferred in an oxidation-reduction reaction? atoms*** electrons ions protons

50. ## physics

A parallel-plate capacitor is formed from two 1.0{\rm cm} \times 1.0{\rm cm} electrodes spaced 2.8{\rm mm} apart. The electric field strength inside the capacitor is 1.0\times10^{6}{N/C}} part a What is the charge (in {\rm nC}) on positive electrode? part

51. ## chemistry

A quantity of electrical charge that brings about the deposition of 4.5 g Al from Al3+ at a cathode will also produce what volume (STP) of H2(g) from H+ at a cathode? I know there are 3 e- difference b/w the two reactions. I took 4.5 g/3 and get 1.5 g H2.

52. ## chemistry

Under an O2(g) pressure of 1.00 atm, 30.9 cm3 of O2(g)at 25C dissolves in 1.00 L H2O at 25C. Assuming that the soln volume remains at 1.00L, what is the Molarity of a saturated O2(aq) soln at 25C when partial pressure O2=1 atm? thank you!

53. ## chemistry

P(s)+ H+ + NO3- ---> H2PO4 + NO + H2O I am trying to write the two half rxns and I can get one, but not the other. I have: red: NO3- +4H+ +3e- ---> NO + 2H2O Ox: P(s) + ? ----> H2PO4- + x e- thank you!

54. ## Chemistry

IGNORE MY FIRST POST. I CORRECTED THIS ONE Write IUPAC name of the following alkanes: 1. (CH3)3 -C-CH2-CH2-CH3 all the numbers are subscripts. So there are 3 CH3's, C,CH2,CH2, and CH3 This is what my teacher has in my homework. The parenthesis really throw

55. ## Chemistry

Write IUPAC name of the following alkanes: 1. (CH3)3-C-CH2-CH2-CH3 Would the name be 2,2-dimethylpentane? Wouldn't it look like this: CH3-C-CH2-CH2-CH3 with a CH3 on the top and bottom of the C, which would be the 2nd carbon... right? I don't understand

56. ## chem

Calculate ΔG° (in kJ/mol) for the following reaction at 1 atm and 25 °C: C2H6 (g) + O2 (g) → CO2 (g) + H2O (l) (unbalanced) ΔGf° C2H6 (g) = –32.89 kJ/mol; ΔGf° CO2 (g) = –394.4 kJ/mol; ΔGf° H2O (l) = –237.13 kJ/mol

57. ## chemistry

Describe the subatomic structure of the nucleus, including the structure of each nucleon. Draw a picture. Describe the forces that hold the nucleus together and draw them on your diagram. Explain how beta emission works.

58. ## chemistry

How do you find the molarity(M) of NaOH in this reaction: 2NaOH(aq) + H2C2O4-H2O > Na2C2O4(aq) + 2H2O The only given information is 0.2079g of H2C2O4-2H2O

59. ## Math

What is the multiplicative inverse of 6 1/7? My answer- 16

60. ## Probability and statistics

Assume that a procedure yields a binomial distribution with a trial repeated n times. Use the binomial probability formula to find the probability of x successes given the probability p of success on a single trial.n=22, x=18, p=0.85, q=.15

61. ## chemistry

The voltaic cell: Pt, H2(g, 1 atm), H+(xM),,H+ (1M), H2(g, 1 atm), Pt registers an Ecell=+0.108 V. What is the pH of the soln? I know that E*cell=0 for this. I was not sure if i place the [xM] on the top of the equation or the bottom of

62. ## Physics

A 10kg box is pulled a distance of 100m along a level floor at constant velocity using a force of 40 N at an angle of 35 degrees above the horizontal. If the box is pulled at constant velocity, what is the coefficient of friction between the bottom of the

63. ## chemistry

Under an O2(g) pressure of 1.00 atm, 30.9 cm3 of O2(g)at 25C dissolves in 1.00 L H2O at 25C. Assuming that the soln volume remains at 1.00L, what is the Molarity of a saturated O2(aq) soln at 25C when partial pressure O2=1 atm? DRBOB222 said to: Convert

64. ## chemistry

The boiling point of water at 735 mmHg is 99.07C. What percent by mass of NaCl should be present in a water soln to raise the boiling point to 100.0C? [Kb for water is 0.512 C kg solvent (mol solute )-1]

65. ## programing

create an algorithm, flowchart, and pseudocode for a solution of the following problem. This solution will include the use of arrays needed to complete all parts of the logic. You have requested to develop a program that will record and process the

66. ## Chemistry

Write IUPAC name of the following alkanes: 1. (CH3)3-C-CH2-CH2-CH3 Would the name be 2,2,4-trimethylhexane? 2. CH3CHCH2CHCH2CH2CH3 with a CH3 attached to the 2nd carbon and the 4th carbon. Would the name be 2,4-diheptane? 3. CH3-C-C-CH3 with a CH3 attached

67. ## physics

a cyclist travels 2.5km east, then 10km south and finally 5km west. determine the cyclist's overall displacement from their starting point.

68. ## Physics

What is one advantage and one disadvantage of using a ramp? Explain in detail.

69. ## Physics

Given: G = 6.67259 × 10−11 Nm2/kg2 . A 602 kg geosynchronous satellite or- bits a planet similar to Earth at a radius 1.98 × 105 km from the planet’s center. Its angular speed at this radius is the same as the rotational speed of the Earth, and so

70. ## chemist geniuses

3. Describe the subatomic structure of the nucleus, including the structure of each nucleon. Draw a picture. Describe the forces that hold the nucleus together and draw them on your diagram. Explain how beta emission works.

71. ## analytical chemistry

Low concentration replicate samples of Pb-EDTA gave the following counts in a mass spectral measurement: 188.3, 145.9, 159.7, 174.7, 143.7, 213.1, 164.7, 169.3, 158.7, 176.3. Ten measurements of a blank had a mean of 27.3 counts. A sample containing 1.00

72. ## Science

Why isn't the fit perfect if the continents were once part of Pangaea?

73. ## survey

what happened to my survey question??? Survey questions are not welcome here; so your question may have been removed. This forum is for homework help. There are other web sites for that sort of thing, such as http://surveycentral.org/survey/25878.html

74. ## chem

which of th gases is obtained industrially by fractional distillation. is it ammonia or chlorine or hydrogen or nitrogen? Nitrogen is obtained industrially by fractional distillation of liquid air.

75. ## Physics

A delivery person pulls a 35 kg box across the floor. The applied force exerted on the box is 122.5 N [38o above the horizontal]. The force of kinetic friction on the box has a magnitude of 55.0 N. The box starts from rest. Using the Work-energy theorem,

76. ## Japanese

How do you write appositives in Japanese? The sentence I have is "The frog who lived in Osaka wished to go to Kyoto, where the great Midako had his palace.

77. ## Physics

A catapult of a spring constant 100N/M contains 2.0J of elastic potential energy when it is pulled back. What is the extension of the rubber band? I know that E= F/K but I don't know how to work out the force from the information provided, help would be

78. ## Chemistry

What is the reducing agent in the following reaction? 2K + S - - > K2S K S*** K2S None of the above

79. ## Physics

What is the smallest radius of an unbanked (flat) track around which a motorcyclist can travel if her speed is 25 km/h and the coefficient of static friction between the tires and road is 0.28?

80. ## Chemistry

IGNORE MY FIRST POST. I CORRECTED THIS ONE Write IUPAC name of the following alkanes: 1. (CH3)3-C-CH2-CH2-CH3 Would the name be 2-dimethylpentane? 2. CH3CHCH2CHCH2CH2CH3 with a CH3 attached to the 2nd carbon and the 4th carbon. Would the name be

81. ## maths

ben bought a car for £12,000 each year the value of the car depreciated by 10% what is the value of the car 2 years after he bought it?

82. ## thermo

equal masses of ice at 0 oC, water aat 50 oC and steam at 100 oC are mixed and allowed to reach equilibrium. what will be the final temp of the mixture? and what percentage is the water and what percent will be steam??

83. ## math

what is 9+10-5°/°2=

84. ## HELP.

Choose a formula for the nth term of the sequence: a2 , a4 , a6 , ... 2 4 8 a^2n 2^n a^2n 2n a^2n 2+n 2^n a

85. ## some science

a filter tip or a cigarette acts as both a filter and a condenser. which of the following cannot be removed, assuming the filter tip is 100% efficient? a. carbon monoxide, boiling point -191 degrees. b. nicotine, boiling point 247 degrees. c. tar, boiling

86. ## chemistry

a bottle of copper(II)oxide has been contaminated with solid sodium chloride, how can the sodium chloride be removed? Copper oxide is totally insoluble in water. The NaCl could therefore be rinsed away. ok.

93. ## Physics

A 599 g piece of silver at 150 degrees C is submerged in 1000 g of water at 5 degrees C to be cooled. Determine the final temperature of he silver and water given Heat capacity of water= 4.18 x 10^3 j/kg degrees C Heat capacity of silver= 2.49 x 10^2 j/kg

94. ## chemistry pH

calculate [H^+] and the pH of 0.025M of HNO3

95. ## physical science

What happens to the gravitational force between two objects if their separation is doubled? The force of attraction is doubled. the same. half as much. one fourth as much.

96. ## math

Initial Investment?? Annual % Rate= 8 Time to Double?? Amount after 10 years= \$20,000 I don't know how to figure out the initial investment and the time to double help me please?

97. ## Chemistry

The reaction of 1,6-hexanediamine with hexanedioic acid chloride to form nylon 6-6 is a condensation polymerization. What is the small molecule that is split off in each step of the reaction?

98. ## Delete Question

Hi! Is it possible to delete a question I asked since I got it answered? Thanks! Subject: Math Date: Monday, March 23, 2015 Time: 8:27

99. ## Physics

An elevator motor provides 45.0 kW of power while lifting a 2000 kg elevator 35 m. If the elevator contains six passengers of the same mass and it takes 20.0 s to accomplish this task, determine the mass of each passenger. Assume the system is 83 %