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M Hasan
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Experience:  BA (Hons) in Mathematics from Oxford University
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Been waiting 3hrs- chemistry questions!!!!

Resolved Question:

hello, I am done with this and received my grade but i want to compare my answers and see where I had the most difficulties. I have only a few hours before i can complete my 2nd round on a different assignment so i would like to get this out of the way so i can do better on my last assignment. I

Hydrocarbons contain only hydrogen and carbon. Which of the following is not a class of pure hydrocarbons? (Points : 4)
       alkynes
       alcohols
       alkenes
       alkanes








2. What prefix is used to name a hydrocarbon with two carbon atoms? (Points : 4)
       Dec-
       Eth-
       Prop-
       Hex-









3. You have two neutral solutions. One contains the indicator methyl red, which turns red in strongly acidic aqueous solutions but is otherwise yellow. The other contains the indicator phenol red, which turns red in strongly basic aqueous solutions but is otherwise yellow. Which of these steps would cause a color change in both solutions? (Points : 4)
       Add a weak acid to both solutions.
       Add a strong acid to both solutions.
       Add a strong acid to one solution, and a strong base to the other.
       Add a weak acid to one solution, and a weak base to the other.









4. Which of the following shows a correctly balanced reaction in which cerium is reduced? (Points : 4)
       Ce3+ (aq) + Fe2+ (aq) -->
Ce4+ (aq) + Fe3+ (aq)
       Ce4+ (aq) + Fe2+ (aq) -->
Ce3+ (aq) + Fe3+ (aq)
       Ce3+ (aq) + Fe3+ (aq) -->
Ce4+ (aq) + Fe2+ (aq)
       Ce4+ (aq) + Fe3+ (aq) -->
Ce3+ (aq) + Fe2+ (aq)









5. Suppose that the gas in a storage tank exerts a pressure of 55.125 lb/in2 . What is the pressure of the gas in units of torr? (Points : 4)
       3.75 torr
       3.799 torr
       41,895 torr
       2850.0 torr









6. In a manometer the mercury level at the open ed of the tube is 215 mm higher than at the closed end of the tube. If the atmospheric pressure is 1 atm, what is the pressure of the gas sample in units of torr?
(Points : 4)
       1.28 torr
       545 torr
       975 torr
       215 torr









7. Using Boyle's Law, predict what will happen to the pressure of a gas in a container at constant temperature, if the volume of the container is changed to one-half its original size. (Points : 4)
       Nothing will happen to the pressure.
       The pressure will be decrease to one-half its original value.
       The pressure will increase to twice its original value.
       More information is needed.









8. A sample of gas is heated. During the heating process, the volume of the gas increases 1.7 times. If the initial temperature of the gas is 80°C, what is the final temperature of the gas? (Points : 4)
       136°C
       600 K
       210 K
       353 K









9. Suppose that you have a 2.0 L sample of hydrogen at 1.00 atm and 59°C. If you heat the sample to 84°C and it expands to a volume of 3.7 L, what will the final pressure be? (Points : 4)
       0.58 atm
       0.76 atm
       0.54 atm
       1.00 atm









10. A helium balloon with a volume of 2.4 L contains 0.10 moles of gas at 25°C and 1 atm of pressure. The balloon leaks 0.02 moles of gas until someone manages to seal the hole. What is the new volume of the balloon? (Points : 4)
       3.0 L
       0.5 L
       19.2 L
       2 L









11. There is an unlabeled gas cylinder in the chemistry lab. The cylinder contains a gaseous compound. A sample of the compound shows that it contains 27.27% carbon and 72.73% oxygen. The 1.50 L bottle was found at STP and contained 2.94 g of the compound. Identify the number of moles of the compound in the bottle. (Points : 4)
       1.96 mol
       0.0669 mol
       0.105 mol
       0.0609 mol









12. Two gas tanks are linked by a connecting tube of negligible volume with a valve. One contains 15 L of nitrogen at 7.2 atm of pressure. The other contains 8.3 L of helium at 4.1 atm of pressure. If the valve is opened, what is the final pressure of the two tanks combined? (Points : 4)
       142 atm
       4.5 atm
       6.1 atm
       0.48 atm









13. Which of the following steps illustrates work being done? (Points : 4)
       A beaker of water being heated from 25°C to 75°C.
       A battery producing 1.5 V.
       A box being pushed up a ramp.
       A log burning in a fireplace.









14. Which of the following has the highest number of Calories? (Points : 4)
       7.2 g of fat
       9.8 g of starch
       15.5 g of sugar
       14.3 g protein









15. What is the sign of q when heat moves from the surroundings to the system? (Points : 4)
       It depends on the value of work.
       Positive
       Negative
       This situation never occurs.









16. Which of the following is true about an endothermic reaction? (Points : 4)
       The reactants have a lower enthalpy than the products.
       The reactants have a higher enthalpy than the products.
       The reactants have the same enthalpy as the products.









17. For the reaction:

6HCl(aq) + 2Fe(s) --> 2FeCl3(aq) + 3H2(g)

Which of the following rate expressions is NOT correct? (Points : 4)
       Rate = -delta[HCl]/6deltat
       Rate = -delta[Fe]/2deltat
       Rate = 2delta[FeCl3]/deltat
       Rate = delta[H2]/3deltat









18. The rate equation for the synthesis of water

2H2 + O2 --> 2H2O

is

Rate = k[H2][O2]

What is the overall order of this reaction? (Points : 4)
       0
       1
       2
       3









19. The following reaction is second order in [A] and second order overall.

2A --> B + C

The instantaneous rate of reaction is 1.8 × 10-3 M/s when [A] is equal to 0.63 M. What is the rate constant, k, of this reaction? (Points : 4)
       1.4 × 10-3 M-1s-1
       2.2 × 102 M-1s-1
       4.5 × 10-3 M-1s-1
       7.1 × 10-4 M-1s-1









20. The activation energy (Ea) on a reaction diagram for an uncatalyzed reaction is generally ________ a catalyzed reaction. (Points : 4)
       the same as
       unrelated to
       greater than
       less than









21. In a reaction, the equilibrium constant for the forward reaction is Kf and the equilibrium constant of the backward reaction is Kb. What is the relationship between Kf and Kb? (Points : 4)
       Kf = Kb
       Kb = 1 + Kf
       Kf = 1/Kb









22.   (Points : 4)
       0.95
       1.05
       0.2
       3.74









23.   (Points : 4)
       The energy of the system will increase.
       More methanol will decompose.
       The equilibrium position will not be affected.
       More methanol will be formed.









24. A simple dissociation reaction is written for each of the following acids. Which one is least correct? (Points : 4)
       Hydrochloric acid:

 



       The ammonium ion:

 



       Acetic acid:

 



       The hydrated aluminum (III) ion:

 












25. What is the [H3O+] in a solution with a pH of 2.34? (Points : 4)
       4.57 x 10-3 M
       4.6 x 10-3 M
       4.57 x 103 M
       4.6 x 103 M









26. A 0.200 M solution of a weak acid, HA, is 9.4% ionized. Using this information, calculate Ka for HA. (Points : 4)
       1.8 x 10-3
       3.8 x 10-3
       9.4 x 10-3
       1.9 x 10-2









27. Which of the following is not a buffer solution? (Points : 4)
       a weak acid (to neutralize a strong base) and its conjugate base (to neutralize a strong acid)
       a weak base (to neutralize a strong acid) and its conjugate acid (to neutralize a strong base)
       a strong acid (to neutralize a strong base) and its conjugate base (to neutralize a strong acid)
       formic acid and sodium formate









28. Which statement about alcohols is not correct? (Points : 4)
       Alcohols contain hydroxyl functional groups.
       Alcohols are organic molecules.
       Alcohols contain nitrogen.
       Alcohols are named by their Greek prefix
+ -anol.









29. Which of the following shows the alkanes in correct order from lowest to highest boiling points? (Points : 4)
       hexane, pentane, butane, propane, ethane, methane
       hexane, ethane, propane, butane, pentane, methane
       methane, ethane, propane, butane, pentane, hexane
       methane, ethane, propane, pentane, butane, hexane









30. Which characteristic defines the main difference between a basic buffer system and an acidic buffer system? (Points : 4)
       A basic buffer system uses more base than acid per liter.
       A basic buffer system is a solution that can maintain an acidic pH when more acid or base is added.
       A basic buffer system maintains a steady basic pH regardless of how much acid or base is added.
       A basic buffer system is a solution that can maintain a basic pH when more acid or base is added.













  

 


 


 


 


22.  



 


  0.95
       1.05
       0.2
       3.74


23.


 



 


    a.The energy of the system will increase.
       b.More methanol will decompose.
       cThe equilibrium position will not be affected.
       d.More methanol will be formed


 




25. A simple dissociation reaction is written for each of the following acids. Which one is least correct? (Points : 4)
       Hydrochloric acid: 

The ammonium ion:

Acetic acid:

  The hydrated aluminum (III) ion: 
Submitted: 2 years ago.
Category: Homework
Expert:  M Hasan replied 2 years ago.
Hi there!

The answers are as follows:

1. alcohols
2. Eth-
3. Add a strong acid to one solution, and a strong base to the other.
4. Ce4+ (aq) + Fe2+ (aq) --> Ce3+ (aq) + Fe3+ (aq)
5. 2850.0 torr
6. 975 torr
7. The pressure will increase to twice its original value.
8. 600 K
9. 0.58 atm
10. 2 L
11. 0.0669 mol
12. 6.1 atm
13. A beaker of water being heated from 25°C to 75°C.
14.
7.2 g of fat
15. Positive
16.
The reactants have a lower enthalpy than the products.
17.
Rate = Δ[H2]/3Δt
18. 2
19.
4.5 × 10-3 M-1s-1
20. greater than
21. Kf = 1/Kb
22. 1.05
23. More methanol will be formed.
24. The hydrated aluminium ion equation
25.
4.57 x 10-3 M
26.
1.8 x 10-3
27. a strong acid (to neutralize a strong base) and its conjugate base (to neutralize a strong acid)
28. Alcohols contain nitrogen.
29. methane, ethane, propane, butane, pentane, hexane
30.
A basic buffer system is a solution that can maintain a basic pH when more acid or base is added.

Hope this helps. If so, please do not forget to click 'Accept'. Any bonus would be great. Thanks! :)
Customer: replied 2 years ago.
I am concerned about a few of the answers, I look at the same set of questions from one of your other experts and some of yor answers are different. I am trying to leard but I am confused on how you both got different answers. How positive are you that yor answers are correct? Can you please try to get back to me soon, like within the next few hours? I would be happy to pay you but I need to know that these are correct.

Thank you!!!
Customer: replied 2 years ago.
I am concerned about a few of the answers, I look at the same set of questions from one of your other experts and some of yor answers are different. I am trying to learn but I am confused on how you both got different answers. How positive are you that yor answers are correct? Can you please try to get back to me soon, like within the next few hours? I would be happy to pay you but I need to know that these are correct.

Thank you!!!
Expert:  M Hasan replied 2 years ago.
Let me know which answers are different and I shall re-check. :)
Customer: replied 2 years ago.
she didnt answer all of them but I think you can compare yours to hers. i copied and pasted them below for you! Thank you so much for the quick response!!!!!!!!!!

1. Hydrocarbons contain only hydrogen and carbon. Which of the following is not a class of pure hydrocarbons?
B. Alcohols

2. What prefix is used to name a hydrocarbon with two carbon atoms?
b. Eth-

3. You have two neutral solutions. One contains the indicator methyl red, which turns red in strongly acidic aqueous solutions but is otherwise yellow. The other contains the indicator phenol red, which turns red in strongly basic aqueous solutions but is otherwise yellow. Which of these steps would cause

c. Add a strong acid to one solution, and a strong base to the other.

4. Which of the following shows a correctly balanced reaction in which cerium is reduced?
b. Ce4+ (aq) + Fe2+ (aq) -->
Ce3+ (aq) + Fe3+ (aq)

5. Suppose that the gas in a storage tank exerts a pressure of 55.125 lb/in2 . What is the pressure of the gas in units of torr?
d. 2850.0 torr

6. In a manometer the mercury level at the open ed of the tube is 215 mm higher than at the closed end of the tube. If the atmospheric pressure is 1 atm, what is the pressure of the gas sample in units of torr?
c. 975 torr

7. Using Boyle's Law, predict what will happen to the pressure of a gas in a container at constant temperature, if the volume of the container is changed to one-half its original size.

c. The pressure will increase to twice its original value.

8. A sample of gas is heated. During the heating process, the volume of the gas increases 1.7 times. If the initial temperature of the gas is 80°C, what is the final temperature of the gas?
b. 600 K

9. Suppose that you have a 2.0 L sample of hydrogen at 1.00 atm and 59°C. If you heat the sample to 84°C and it expands to a volume of 3.7 L, what will the final pressure be?
b. 0.76 atm

10. A helium balloon with a volume of 2.4 L contains 0.10 moles of gas at 25°C and 1 atm of pressure. The balloon leaks 0.02 moles of gas until someone manages to seal the hole. What is the new volume of the balloon?
d. 2 L

11. There is an unlabeled gas cylinder in the chemistry lab. The cylinder contains a gaseous compound. A sample of the compound shows that it contains 27.27% carbon and 72.73% oxygen. The 1.50 L bottle was found at STP and contained 2.94 g of the compound. Identify the number of moles of the compound in the bottle.
b. 0.0669 mol

12. Two gas tanks are linked by a connecting tube of negligible volume with a valve. One contains 15 L of nitrogen at 7.2 atm of pressure. The other contains 8.3 L of helium at 4.1 atm of pressure. If the valve is opened, what is the final pressure of the two tanks combined?
c. 6.1 atm

13. Which of the following steps illustrates work being done?
c. A box being pushed up a ramp.

14. Which of the following has the highest number of Calories?
a. 7.2 g of fat

15. What is the sign of q when heat moves from the surroundings to the system?
b. Positive

16. Which of the following is true about an endothermic reaction?
a. The reactants have a lower enthalpy than the products.

17. For the reaction: 6HCl(aq) + 2Fe(s) --> 2FeCl3(aq) + 3H2(g)

Which of the following rate expressions is NOT correct?
c. Rate = 2 [FeCl3]/ t

18. The rate equation for the synthesis of water

2H2 + O2 --> 2H2O is Rate = k[H2][O2]

What is the overall order of this reaction?
d. 3


19. The following reaction is second order in [A] and second order overall.

2A --> B + C

The instantaneous rate of reaction is 1.8 × 10–3 M/s when [A] is equal to 0.63 M. What is the rate constant, k, of this reaction?
c. 4.5 × 10–3 M–1s–1

20. The activation energy (Ea) on a reaction diagram for an uncatalyzed reaction is generally ________ a catalyzed reaction.
c. greater than

21. In a reaction, the equilibrium constant for the forward reaction is Kf and the equilibrium constant of the backward reaction is Kb. What is the relationship between Kf and Kb?
c. Kf = 1/Kb

22. Please respond to the answer with this question it was not entered

23. There was no question, respond to the answer and I will be happy to answer it for you

25. What is the [H3O+] in a solution with a pH of 2.34?
a. 4.57 x 10–3 M

26. A 0.200 M solution of a weak acid, HA, is 9.4% ionized. Using this information, calculate Ka for HA.
c. 9.4 x 10–3

27. Which of the following is not a buffer solution?
c. a strong acid (to neutralize a strong base) and its conjugate base (to neutralize a strong acid)

28. Which statement about alcohols is not correct?
c. Alcohols contain nitrogen.

29. Which of the following shows the alkanes in correct order from lowest to highest boiling points?
c. methane, ethane, propane, butane, pentane, hexane

30. Which characteristic defines the main difference between a basic buffer system and an acidic buffer system?
d. A basic buffer system is a solution that can maintain a basic pH when more acid or base is added
Customer: replied 2 years ago.

The ones in red i want to be sure are correct. I am not doubting you I just want to be sure I am learning it correctly. :)


1. alcohols
2. Eth-
3. Add a strong acid to one solution, and a strong base to the other.
4. Ce4+ (aq) + Fe2+ (aq) --> Ce3+ (aq) + Fe3+ (aq)
5. 2850.0 torr
6. 975 torr
7. The pressure will increase to twice its original value.
8. 600 K
9. 0.58 atm
10. 2 L
11. 0.0669 mol
12. 6.1 atm
13. A beaker of water being heated from 25°C to 75°C.
14. 7.2 g of fat
15. Positive
16. The reactants have a lower enthalpy than the products.
17. Rate = Δ[H2]/3Δt

a Rate = -[HCl]/6t

bRate = -[Fe]/2t

c Rate = 2[FeCl3]/t this was my answer

d.Rate = [H2]/3t your answer?


18. 2
19. 4.5 × 10-3 M-1s-1
20. greater than
21. Kf = 1/Kb
22. 1.05
23. More methanol will be formed.
24. The hydrated aluminium ion equation
25. 4.57 x 10-3 M
26. 1.8 x 10-3
27. a strong acid (to neutralize a strong base) and its conjugate base (to neutralize a strong acid)
28. Alcohols contain nitrogen.
29. methane, ethane, propane, butane, pentane, hexane
30. A basic buffer system is a solution that can maintain a basic pH when more acid or base is added.

Expert:  M Hasan replied 2 years ago.
Hi there!

None of them seem to be in red. Can you mention the question numbers?
Customer: replied 2 years ago.
sure, sorry they are in red when I lok at them. Hold on

7. The pressure will increase to twice its original value.

9. 0.58 atm

13. A beaker of water being heated from 25°C to 75°C.

12. 6.1 atm

17. Rate = Δ[H2]/3Δt

18. 2

24. The hydrated aluminium ion equation
25. 4.57 x 10-3 M
26. 1.8 x 10-3

Expert:  M Hasan replied 2 years ago.
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M Hasan, Teacher
Category: Homework
Satisfied Customers: 1849
Experience: BA (Hons) in Mathematics from Oxford University
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Customer: replied 2 years ago.
Great!!!! Thank you!

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