# 1. Determine the overall reaction order for the reaction whose rate law is as follows: rate=k[O3][ClO]:

a. 0
b. 1
c. 2 ***
d. 3

2. For the reaction (A→2B) whose rate law is rate=k, which of the following will change the value of k?
a. adding a catalyst
b. increasing [A]
c. increasing [B] ***
d. decreasing [B]

3. If the sign of a reaction rate is positive, that means
a. The reaction does not go in the reverse direction.
b. It must be the rate for the appearance of a product. ***
c. The reaction is an endothermic reaction.
d. The reaction is an exothermic reaction.

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1. I agree with 1 and 3 but not 2. Hint: The secret to question 2 is to write the rate law equation.

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DrBob222
2. Would it be (b) increase [A] for # 2?

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3. I gave you a hint. What is the rate law equation?

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DrBob222
4. Idk if this is right--k= [A]^1 [B] ^2.

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5. That is almost right.
You don't know the exponents are 1 and 2.They must be determined experimentally. So let's write it as rate = [A]^a[B]^b
Now you know from the problem that rate = k so what must a be and what must b be for rate = k?

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DrBob222
6. I'm not sure how to determine experimentally. is it [A]^0 [B]^1?

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7. close but no cigar. Think about it.
For the rate law of rate = k[A]^a[B]^b, the ONLY way rate = k is for [A]^a[B]^b to be 1; i.e., rate = k*(1)*(1) and the ONLY way [A]^a = 1 is for a to be zero. Likewise b must be zero for [B]^b = 1 so the equation is
rate = k[A]^0[B]^0 = k(1)(1) = k. That means that the rate does not depend on [A] OR [B] because NEITHER A nor B are in the rate equation so the correct answer must not have anything to do with [A]
or [B]. So the correct answer must be ...........

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DrBob222
8. Oh, if it has nothing to do with [A] or [B] is the answer (a) adding a catalyst?

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9. bingo

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DrBob222