# chemistry

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A first-order reaction initially proceeds at a rate of 0.5 mol/ls. What will be the rate when half the starting material remains? When one-fourth of the starting material remains?

• che,istry -

Isn't the rate for a first order reaction rate = k[A]?.
rate = 0.5
Make A anything and solve for k.
Then use rate = k[A].
you know k and [A] now is 1/2. Then 1/4. solve for rate for each. Check my thinking.

• chemistry -

I think that is good cause the rate is proportional to [A] as it is first order?

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