1. chemistry

determine the vapor pressure of a solution at 55 degrees C that contains 34.2g NaCl in 375 mL of water. The vapor pressure of pure water at 55 degrees C is 118.1 torr. so Psolution=XsolventPsolvent I don't know why I'm not getting the correct answer... so

2. chem

HOw much energy is required to heat 36.0g H2O from a liquid at 65C to a gas at 115C? The following physical data may be uselful. Hvap=40.7kJ/mol C liquid=4.18 C gas=2.01 C solid= 2.09 T melting=0 C T boiling=100 C The answers about 87.7 kJ However I'm not

3. chem

Calculate the mole fraction of total ions in an aqueous solution prepared by dissolving .400 moles of MgCl2 in 850.0g of water. mole fraction =amount solute(in mols) /total amount of solute and solvent (in mols) so wouldn't it be .400/ .400+ 47.2 which is

4. chem

which of the following substances should have the highest melting point? Xe F2 SrS MgO CO2 the answers D, is it because its an ionic compound?

5. science

Does sugar crystals grow faster in tap water or distilled water?

6. physics

A 2 kg block, starting from the rest, slides 20 m down frictionless inclined plane, dropping a distance of 10m. The magnitude of the net force on the block while it is sliding is...? How do I solve this problem? And if it were to ask for the speed at the

7. chemistry

write the balanced half reaction for the conversion of Cl2(g)to Cl-(aq)

8. English; grammar

Could you please tell me if I have properly identified the part of speech of each word. If I have made a mistake, could you please correct me. - Word: femurs Sentance:Jawbones, hipbones, femurs. Part of Speech:NOUN Word: Apache Sentance: White smoke puffed

9. chemistry

Using a BCA table, calculate the molarity of a 25.0 mL sample of HNO3 that's is titrated to its endpoint with 22.7 mL of 0.200 M NaOH.

10. i hate.."chemistry"

write the balanced half reaction for the conversion of HOBr(aq) to Br2(aq) in acidic solution

11. health care

Why is economic issue a problem to the aging population?

12. math

Factorise:- 27p^3-1/216-9/2p^2+1/4p

13. financial resources

Assignment Type: Discussion Board Deliverable Length: 2-3 paragraphs Points Possible: 55 Due Date: 5/18/2008 11:59:59 PM CT Bob Brown was recently involved in a minor auto accident. His car was hit from behind, and he, in turn, slammed into the car in

14. chemistry

The specific gravity of a sample of concentrated nitric acid is 1.42. What is the volume in liters at 20oC occupied by 145.3 g of this concentrate nitric acid?

15. Physics

A 10kg block is attached to a massless cord that doesn't stretch or sag which is rapped around a disc like wheel, m=5Kg, I= (1/2)mR^2. If the block is allowed to drop straight down held back only by the rotation of the wheel: 1. What is the tension of the

16. science

write the balanced half reaction for the conversion of CL(g)to Cl-(aq)

17. precalculus

A force of 369 lbs makes an angle of 18 degrees 20 minutes with a force 427 lbs. Find the angle made by the equilibrant with the 369 lbs force. I know I can find this using the law of cosines, but I think my teacher wants me to use some vector thing, but I

18. chem

In the reaction of calcium metal and water, 50.0 mL of hydrogen gas is collected over water at 25.0 degrees C with a total pressure of 752 mmHg. Calcualte the number of moles of hydrogen gas that was produced. Do we just plug this into n=pv/rt ? or is

19. French

Good evening Could you please check if i have written these sentences corretly into french. Thank a billion. 1 I will feel very sad and lonely in the dungeon. I would miss the outdoors, friends and my family. (Je me sentirai très triste et seul dans le

20. English 102(writing in the discipline)

I have a problem bout my subtopic of my research paper. This is my Outline The Importance of Networking in Business Networking is the most effective way in making your business grow faster. I. Importance of networking in business II. Types of network used

21. chem

determine the oxidation number of MgBR2(s) and NH4No3(s)

22. social std.

How was Louis XVI responsible for out- berak of Freanch Revolution ?

23. algebra

THe length of a rectangle is twice the width. The area is 200yd^2. What is the length and width. Is this right L=20 w=10

24. Statistics

Suppose you conduct a study and find that the probability of having a baby boy is 60%. Now suppose three of your relatives are going to have babies. a) Build a tree diagram showing all the conditional probabilities and joint probabilities associated with

25. algebra

The number of tickets soldeach day for an upcoming performance of Handiel Messiah is given by N(x)=-0.4x^2+9.6x+10,where x is the number of days since the concert was first announced. WHen will daily ticket sales peak and how many tickets will be sold that

26. French

Good afternoon, Could you please help me make sure i have translated these sentences correctly. 1)Comment tu te sentiras dans le cachot (qui ou qu'est-ce que vous manquerez le plus) -How you will feel in the dungeon (which or what you will miss more)?

27. Math

How do you graph the quadratic formula x^2-10x=11? Here's what I got so far: In standard form, it's x^2-10x-11=0. Discriminant: -10^2-4(1)(-11)=144 Axis of Symmetry: 10^2/2(1)=50 Quadratic Formula: 56 and 44 Thank You!

28. Math, derivatives

Let g(x) = sin (cos x^3) Find g ' (x): The choices are a) -3x^2sinx^3cos(cos x^3) b) -3x^2sinx^3sin(cos x^3) c) -3x^2cosx^3sin(cos x^3) d) 3x^2sin^2(cos x^3) I'm not exactly sure where I should start. Should I begin with d/dx of sin? Or do the inside

29. chemistry

For which trial(s) is phenophthalein a good indicator? For which trial(s) was it a poor indicator? For those trials in which it was a poor indicator, suggeest a better indicator and indicate its pH range on the titration curve. So for phenophthalein the

30. science

which physics principles are employed in stopping a runaway truck in a gravel and sand ramp at the bottom of a mountain?

31. Spanish

Please correct my work please: This is what I'm working on: Command form(imperative mood)negative familiar/polite. I have to change the following affirmative commands to the negative form. (write the word no, the object pronoun(s), and the negative command

32. home economics

Critically assess the HDI as a measure of development. What do you think should be added to the HDI to measure development? Using an example and creating some new spheres or indices within the HDI, create an example showing how countries might rank with

33. math

justin had \$49 before spending y dollars on jeans. How much money remains

34. Math

For all real numbers, f(x)=(x^2+1)/2. If f(a)=25 and f(11)=b, what could be the value of b-a? I'm confused on how you do these problems. Can someone show me how to do them? Thanks much!

35. Chemistry, electrochem

(1) Half-reactions are written as ______ reactions with charge and mass balanced. (2) Among the ions, Cd^2+, Pb^2+ & Ca^2+, ________ has the greatest ability to reduce to its neutral metal. (3) Among the neutral metals; Pb, Ca & Cd, ________ has the least

36. RE: Spanish

I have a PC, not Mac. And I tried to answer them in the best of my ability. The thing that really threw me are the reflexives. Enciendamela ahora = No me la Encienda Inscribete en ese curso = (still unsure) Quitatelos antes de comer = No los Quitates

37. statistics

you have 8 blue marbles, 7 red marbles, and 5 green marbles. What is the probability of obtaining at least 2 red marbles in three draws with replacements? I have the answer, just can't figure out how to get it. Thanks!

38. math

I need help with a question... In this case k and l are parallel lines and contain the given points of: k=(2,5),(8,14) and l=(5,3),(11,y)... how do I calculate for y? Please help!

The perimeter of a rectangle is 150 ins. The length is 3 ins. longer than 5 times the width. Find the length. A)63 B)12 C)36 D)38

40. chem

write the balanced half-reaction for the conversion of Fe(s)to Fe+2(aq)

41. mathematics

If 3xy^3 - 4x = 10y^2, find y ' (x) a) (4 + 3y^2)/(9xy^2 + 20y) b) (4 - 3y^2)/(9xy^2 - 20y) c) (3 + 4y^2)/(20xy^2 + 9y) d) (3 - 4y^2)/(20xy^2 - 9y)

42. SCIENCE

How many types of catalists are there ? Name each of them.

43. health care

what are three issues faced by the aging population that you believe to be a problem? any ideas please?

44. home economics

You are gathering demographic data in a village. You suspect that families have a gender bias; that is, they have children until a certain target number of sons are born, but you don’t have direct evidence of this. All you have is information on the sex

45. math... help me.. please =)

Hello. I'm learning about simplying radicals and in one of the questions it has a variable to the second power like below: 1) square root of 28x^2 2) square root of 25x^2 3) square root of 80n^2 Can you answer at least one of them and explain what you did?

46. english

I'm having trouble paraphrasing this: Einstein used his light-quantum hypothesis to explain another important puzzle, the photoelectric effect. Can you help?

48. alg 2

write an equation for the conic section Ellipse with vertices at (-2,2)and (4,2) and covertices at (1,1) and (1,3)

49. English

Ms. sue I am writing a paper on cost of food today. Where can I find graph or table showing the increase in price for food and gasoline. Please help. Rose

50. science

Is there a relationship between ozone depletion and global warming?

51. chemistry

Draw three repeating units of the condensation polymer made from ethanedioic acid and ethanediol.

52. NEED INFORMATION

DO YOU KNOW WHERE I COULD GET INFORMATION ON THE DEVELOPMENT AND CHALLENGES OF THE HEALTH AND EDUCATION SYSTEM IN GUINEA, WEST AFRICA, SINCE IT'S INDEPENDENCE?

53. Accounting Question

Below are two questions from my accounting class. I am not sure how to approach this kind of problem. Any help or suggestions would be greatly appreciated. Thanks in advance! ------------------------------ The following trial balance of Trane Corp. at

54. Science / Biology

How does modern science explain the evolution of abiotic to biotic matter? How would the first life form have survived in the first day / week of its formation? What kind of system of organelles / biological functions would it have to form in the first day

55. English

I need a source bout the "Importance of networking in business" thank you very much to all the experts..

56. algebra

A student opens a mathmatics book to two facing pages. The product of the page numbers is 2352. Find the page numbers.

57. History

How was Charles II involved with the Royal Society and science in general?

58. Electronics/Circuits

Just a simple one... which symbol should I use to represent a strain gauge on circuit diagram? Thanks

59. chemistry

Suggest a type of reaction and the conditions required to breakdown polyamides into their monomers.

60. French

Could you please see if i have translated the following sentences correctly. Thanks 1. Five objects I would choose to have in my dungeon are (Cinq objets que je choisirais d'avoir dans mon cachot sont) 2. A computer to keep in contact with friends and

Do tariffs help protect American Jobs and wages

62. Biology

What are the biological interrelationships among the life forms in the Galapagos Islands?

63. hardware

Why is it recommended to establish a formal evaluation criterion when considering the purchase of hardware for the organization?

64. computers

a) Different types of storage devices are optimal for different situations. Explain what situations are appropriate for the following devices and explain why: Hard disk Floppy disk RAM CD ROM Tape b) Explain the role of each of the following in determining

65. Biology

What protections are already in place to safeguard and preserve the Galapagos Islands?

ugh please help me, im having such a huge stress over this! Le premier arrondissement de Paris est le plus petit et assez historique. Il a été créé le 24 mars 1852. Le population du premier arrondissement était approximativement de quatre-vingt dix

I thought I was understanding this but I am really not sure about the symbols. Does the 3*(13/20)^2*(7/20) translate to 3 times 13/20 times 2 times 7/20? Sorry I am not up on the symbols... I will keep trying.

68. chem

assign oxidation numbers to PF-6(aq)

69. science

why well is built in a shape of circle?

70. human life

Why in acient period people live more than the life span ???

71. capital markets

Hi can anybode help me in this question....With one numerical example show how government bonds are priced and their yields are calculated, and also explain how they provide the benchmark for the cost of funds for other borrowers?

72. Economic Management Scients

What is 'improper' tax which we get in South Africa?

73. Healthcare Technology

Analyze disaster vulnerabilities in health care and human service organization. Write a vulnerability assessment report for an urban medical clinic serving low-income clientele as if you were a consultant. The clinic is located in the hot, dry desert