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STLRamsFan
October 28th, 2011, 03:31 AM
Hey guys, would you mind checking my answers to see if I'm good to go? I'm pretty sure I'm fine (then again I've been messing up a lot on simple stuff on the darn things) but just want to be sure. Forgot to send the last homework assignment in, so doing well on this one is important.
Thanks!

Which of the following statements best describe an example of kinetic energy?
A) car battery
B) sunshine
C) a muscle flexing
D) an energy bar

My answer: A

The nutritional label on a can of chicken noodle soup indicates that each serving contains 1.5 g fat, 8.0 g carbohydrates, and 3.0 g protein. How many total Calories are in a serving?

A) 58 Cal
B) 58 cal
C) None of the above

My answer B (since the symbol is cal not Cal)

Which of the following reactions best illustrates an endothermic reaction?

A) Si(s) + 2 Cl2(g) → SiCl4(g) ΔH = -157 kcal
B) A chemical hot pack used as a hand warmer
C) Ca(OH)2 (s) + 65.3 kJ → CaO(s) + H2O(l)

D) Burning natural gas in a Bunsen burner




My answer A

Which of the following would NOT affect the rate of a reaction?

A) heating the reaction
B) adding a catalyst
C) adding more reactants
D) using a beaker instead of a flask

My answer C

Which of the following terms would be in the product(s) for the correctly balanced equation if the equilibrium expression is:
[CO2]2/[CO]2[O2]



A) CO2


B) O2
C) 2 CO
D) CO 2

My answer A

Which of the following equilibrium constants would be the least enough of product formed in a reaction?

A) 8.9 X 10^14
B) 5.1 X 10^6
C) 1.3 X 10^-3
D) 9.4 X 10^-8

My answer D (?)

Which term in the following reaction would not be included in the equilibrium expression?
2 Na3PO4 (aq) + 3 MgCl2 (aq) → 2 Mg3(PO4)2 (s) + 6 NaCl (aq)

A) MgCl2
B) Mg3(PO4)2
C) Na3PO4
D) NaCl

My answer A

What effect would be seen if additional nitrogen gas was added to the following reaction:
N2 (g) + 3 H2 (g) → 2 NH3 (g) + 22 kcal

A) The amount of energy given off will increase
B) the concentration of ammonia would decrease
C) the concentration of hydrogen gas would increase
D) The equilibrium would shift to the left

My answer: ? We never went over this....

Which of these statements is NOT true when a human is subjected to cold temperatures?

A) shivering cause the muscles to generate more heat
B) reactions in the body slow down
C) blood vessels dilate to help dissipate heat
D) blood vessels in the extremities constrict to reduce the loss of heat

My answer C

In an exothermic reaction, which of the following would cause the reaction to shift to the right?

A) add product
B) raise the temperature
C) add reactant
D) add a catalyst

My answer C
__________________________________________________ _____________________________


I just have that gut feeling I have a few things wrong. Need to know since I have a quiz coming up next week and want to see if I'm on the right track or not. Thanks for the help. Definitely appreciate it!

EagerYoungSpaceCadet
October 28th, 2011, 01:51 PM
First is C.

Dunno the energy value... whatever so IDK about 2.

I'd say that 3 is C, because the system recieves heat (hence the +65.3 kJ).

You got 9 right.

I haven't got a clue about the rest! Luckily, I don't even have to know anything about it yet

STLRamsFan
October 28th, 2011, 03:58 PM
Yea I agree with you on the first one. Someone told me that the second one is C even though I calculated it at 58 calories... Even the third one I was told was A from another.. Number 9 is definitely right, looked it up to be sure and that confirmed it.

Which that being said here's what I have for a revised selection of answers since it looks like I brain farted on quite a few of them (I did them late at night so throw me a bone...):

C
B
A
C
C
A
A
?
C
C

How am I doing so far? Having that gut feeling I have a few wrong.