# Questions Asked onJune 20, 2009

1. ## chemistry

what do you observe in the displacement reaction of zinc and lead nitrate? also, what is the symbol equation for this reaction?

2. ## chemistry

A mixture of hydrogen peroxide, H2O2, and hydrazine, N2H4, can be used as a rocket propellant. The reaction is: 7 H2O2(g) + N2H4(l) ® 2 HNO3(aq) + 8 H2O(l) a) How many moles of H2O2 react with 0.477 mol N2H4? [1] ___________ b) How many grams of HNO3 can

3. ## Organic chemistry

compound with a molecular formula C8H16O has the following H-nmr spectrum: 3H triplet at 0.90, 1.0 to 1.6 8H multiplet, 2.05 3H singlet, 2.25 2H triplet. What is the structure of this compound? I think it is 2-octanone but not sure

4. ## physics

can you show me how to do this mathematically A car traveling 90 km/h is 100 m behind a truck traveling 75 km/h. How long will it take the car to reach the truck?

5. ## University math grade 11 Trig

A very tall light standard is swaying in an east-west direction in a strong wind. An observer notes that the time difference between the vertical position and the furthest point of sway was 2 seconds. The pole is 40 metres tall. At the furthest point of

6. ## Chemistry

If you add Na2CO3 and AgNO3 together in a test tube what exactly would you observe and what would be the equation for the equilibrium system? If you then add HNO3 to the solution what exactly would you observe and what would be the equation for that

7. ## economics

Explain this statement: the most unlikely problem of the national debt is that the government will go bankrupt.

8. ## Math

Use the substitution method to find solution sets (x,y) for the following systems of equations: 3x-5y=-11 6x+2y=26

9. ## medical billing and coding from Penn Foster

I am writing a research paper for HIPAA, I beleive I have most of the information to do the paper. I do not understand what it means by writing it in proper MLA/APA citation style? Could someone please explain this to me and show me a small example of what

10. ## mat115

A rectangular picture window is 6 ft by 4 ft. Polly wants to put a trim molding around the window. How many feet of molding should she buy?

11. ## chemistry

what exactly would you observe and see at the end of the reaction of zinc and lead nitrate? include in formation about colour changes and bubbles. you can use the following equation to help; zinc+lead nitrate(arrow) zinc nitrate+lead

12. ## chemistry

A 10.0 mL sample of 3.00 M KOH(aq) is transferred to a 250.0 ml volumetric flask and diluted to the mark. It was found that 38.5 ml of this diluted solution was needed to react the stoichimetric point in a titration of 10.0 mL of a phosphoric acid, H3PO4,

13. ## chemistry

does this sound right for what happens with the zinc and lead nitrate reaction? could i add anything else? The zinc displaces the lead. You can observe the lead preipitating on the zinc surface. The zinc changes to black crystals which dissolve in the

14. ## Physics

The last stage in the fusion of hydrogen to form helium in the Sun involves the formation of an alpha particle (4He) from two 3He nuclei: 3He + 3He 4He + p + p The binding energy for 3He is 2.57 MeV per nucleon and that for 4He is 7.07 MeV per nucleon.

15. ## maths

make the letter in the bracket the subject of the formulae: v=u-3t (t) a=b-4c (c)

16. ## Physics

You are told that the volume of a sphere is given by V=(sqrt)d^3/4, where V is the volume and d is the diameter of the sphere. Is this equation dimensionally correct?

17. ## chemistry

why does zinc and lead nitrate react?

18. ## Physics

Would someone check this please? A circular loop of wire of radius 0.10 m and of resistance 2.0 x 10^−3 ohms is in a region where there is a uniform magnetic field B. The field is at 30deg to the normal to the plane of the wire loop as shown in Figure 3.

19. ## Math

Name the property that justifies each step. [(2x100)+(3x10)]+[(1x100)+(5x10)] = (2x100)=[(3x10)+(1x100)]+(5x10) I think this is Commutative = (2x100)+[(1x100)+(3x10)]+(5x10) I think this is Distributive property =[(2x100)+(1x100)]+[(3x10)+(5x10)] I think

20. ## analysis and design

5.2 Project Risks [Use this section to list at least five risks factors and their potential impacts for the project.] # Risk Area Likelihood Risk Owner Project Impact-Mitigation Plan 1 [Project Risk] [High/Medium/Low] [Replace this text with a description

21. ## Phoenixuniversity

How did you come up with answers to Comprehensive Grammar Checkpoint

22. ## Literature Help quick question

In the book you don't know me by david klass does anyone know what John's stepfather name was? I think it was Stan but I'm not sure.

23. ## maths

make v the subject of the formulae: v=2v+3u

24. ## physics

the speed of a car can be measured in s^-1 m right... it could be said that a speed of a car the velocity was 15 s^-1 m which is perfectly acceptable... by definition 15 s^-1 m can also be written as 15 Hz m just by definition... what on earth does that

25. ## Helth

700 words paper evaluating the financial aspects of the Wic Program How do they fund their programs? o How reliable are their funding sources? o Do they implement financial accountability measures to ensure that funds are being used properly? o What

26. ## math

Show that any positive odd integer is of the form 6q+1, 6q+3 or 6q+5, where q is any positive integer

27. ## chemistry

Long but quick chemistry lab that I need confirmation on answers if possible? OK so I have this lab that went pretty quick and smooth and I have an online assessment that I needed to put all my figures in. I am all complete but am having trouble with 3

28. ## Physics

A racecar driver in an 825-kg car accelerates from rest to a velocity of 21.5 m/s in 0.55 s. What is the net force acting on the car? I found out using A=v/t that the horizontal acceleration is 39.1 m/s^2. My problem now is this... Is the net force just

29. ## analysis and design

My project is upgrading a bathroom and this is what I need help with: Project Risk-list 5 factors and their potential impact for the project. Project Constaints-ex: triple constaints variable (cost,time/schedule and scope)are there any possible limitations

30. ## Math

What does relative to math?

31. ## math

b. A number is divisible by 8 if it is divisible by 4 and divisible by 2.

Which government entities regulate the securities that Verizon issues?

Which investment bank does Verizon use to issue stock?

Which two lenders does Verizon use?

35. ## math

If a number is divisible by 4 and 6, it must be divisible by 24

36. ## elementry math

How do the ideas of divisibility and multiples relate to the study of fractions?

37. ## Algebra

Given that f(x) = x^2-3 and g(x) = 2x+1 find each of the following if it exists. (g/f) (-1/2)

38. ## lewis structure for molecules

HELLO, I AM LOOKING FOR ONLINE EXERCISES/WORSHEETS TAT I CAN USE TO PRACTISE HOW TO DRAW lewis structure for molecules. I AM LOOKING FOR RELABLE SOURCES, I DON'T WANT TO USE JUST ANY WEBSITE BECAUSE I'M AFRAID THEY WILL CONTAIN ERRORS? COULD SOME ONE

39. ## re

what is the miracle of Lourdes? is it about the young girl called Bernadette? thanks

40. ## Math

Can someone help me with this problem? Evaluate the numerical expression on a calculator. Round the answer to the nearest whole number. ( 34*15) (364) -------- * ---- (5) (52) Here is what I figured: (510) (364) -------- * ----- (5) (52) = (185640) -------

41. ## Maths ...

Hi Can anyone help with this little problem , I have to compare the percentage change for the following numbers from a graph (Tonnes) Comparing the lower years with the year 2050 Year 2050 = 14672.873 2046 = 14745.197 1990 = 6096.0 I have worked out the

42. ## Algebra

Please Help! Confused! I got an answer but it is not correct. Can someone help? Thanks! Given that f(x) = x^2 - 3 and g(x) = 2x + 1, find each of the following, if it exists. (gf) (-1/2)

43. ## Physics

when trying to find uncertanty percent error and your given the number - 15 s^-2 m with a implied uncertanty of +/- 1 s^-2 m and you try to find the percent uncertanty and you do this (- 15 s^2 m)^-1 1 s^-2 m (100 %) is the percent negative or positve also

44. ## designs

nice henna/mehndi designs....? didn't find any interesting ones on google

45. ## math

Show that any positive integer is of the form 4q, 4q+2, where q is any positive integer.

46. ## Algebra

y = (1+x)/(1-x) How do I rearrange that equation to be: x = (y-1)/(y+1)

47. ## english

on an exam if you are given an essay to read & then deconstruct.....how do you do this Thanks

48. ## health care

Where do you think health care quality will be ten years from now?

49. ## math

The following conjectures were made by students. Which do you think are false? Give a counterexample for each conjecture if possible. a. Only half of the nonzero even numbers up to 100 are divisible by 4.

50. ## math

c. If 12 divides a number, 6 also divides the number.

51. ## math

A customer wants to make a teepee in his back yard for his children. He plans to use lengths of PVC plumbing pipe for the supports on the teepee, and he wants the teepee to be 12 feet across and 8 feet tall. How long should the pieces of PVC plumbing pipe

52. ## Sci275

I am doing my final project on energy conservation.What are some good resources on energy conservation?