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10 points! Chemistry- Spontaneous reactions- 2 Questions! Just tell me if my answers are correct! Pleaaase!?

1) Under standard conditions, (298 K and 1 atm), which statement is true?

a) Diamond converts to graphite spontaneously

b) Graphite converts to diamond spontaneously

c) None of the above.

2) How can the spontaneity of a reaction be reversed?

a) Increase the temperature

b) decrease the temperature

c) none of the above

For number 1, I think it is a because the delta G of the reaction is negative but I am not sure. I think number 2 is B because if you decrease the temperature, you might need to put in energy to make a reaction happen?

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This is the Correct answer for this question.

I think 1 is c because as far as i know under standard conditions it takes a very long time for graphite to convert into diamond.(So its not spontaneously.)

And for the second one i think the answer is b because by decreasing the temperature you also decrease the energy of the reaction.And by decreasing the temperature you can reverse the spontaneity of the reaction.

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This is the Correct Answer

1) Under standard conditions, (298 K and 1 atm), which statement is true?

a) Diamond converts to graphite spontaneously

b) Graphite converts to diamond spontaneously

c) None of the above.

The true statement is (a). ΔG is negative. But don't worry about your diamond collection. While the reaction is spontaneous, it is also very S-L-O-W. "Spontaneous" in chemistry does not mean "spur of the moment", but instead, it means that something can happen without outside influence.

2) How can the spontaneity of a reaction be reversed?

a) Increase the temperature

b) decrease the temperature

c) none of the above

You should add a fourth choice (d) either of these. Depending on whether the reaction is exothermic or endothermic, changing the temperature can cause a spontaneous reaction to become nonspontaneous or vice versa.

ΔH .... ΔS ..... ΔG (ΔG = ΔH – TΔS)

- …..... + ....... always negative (always spontaneous)

- .…......- ........ negative at low temperatures (pos at high temp)

+ ….....+ ........ negative at high temperatures (pos at low temp)

+ ….....- ........ always positive (always non spontaneous)

====== Follow up ======

Zeyo is missing the meaning of "spontaneous" and it is because of the way the word is often used in todays speech. "Spontaneous" is sometimes used to refer to something that is "spur of the moment" which implies a "fast decision". That is not the way the word "spontaneous" is used in chemistry. A spontaneous chemical process occurs with no outside intervention. And while a reaction may be spontaneous, it doesn't have to occur "on the spur of the moment." It may take a really long, long time because the reaction is so slow. Kinetics and thermodynamics give us different information

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sapling HW answer

which was correct

1) Diamond converts to graphite spontaneously

2)none of the above

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