# chemistry

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The half-life of a reaction was found to be inversely dependent on the concentration of the starting material. Thus, we can say that

a. the reaction is zero order b. the reaction is first order c. the reaction is second order

d. the reaction starts out first order and changes to second order after one half-life.

e. the reaction starts out second order and changes to first order after one half-life.

Need some help

chemistry - DrBob222, Friday, February 17, 2012 at 10:04pm
Write these down some place where you can keep it until you can (a) derive them or (b) memorize them.
half life:
zero order is (Ao)/2a*k

order 1 is 0.693/ak

order 2 is 1/a*k*(Ao)

both a and k are constants; a is the coefficient and k is the rate contant.
(Ao) = initial concn

chemistry - elvis, Saturday, February 18, 2012 at 8:33pm

need step by step solution and answer because i have no idea how to do this!

• chemistry - ,

I GAVE you a step by step solution. Here is the question.
The half-life of a reaction was found to be inversely dependent on the concentration of the starting material. Thus, we can say that

I gave you the three possibilities. zero order, 1st order, 2nd order. (I didn't include orders higher than that because they usually don't happen.). Now, read the problem and see which answer fits the question. ",.....was found to be INVERSELY dependent on the CONCENTRATION of the STARTING MATERIAL."
Only one of those three possible answers shows the starting material in the denominator.

• chemistry - ,

558.7