Problem

A certain reaction has

k = 0.025 \text{ Ms}^{-1}

for the disappearance of A. What will be the concentration of A after 15 seconds if the initial concentration is

0.50 \text{ M}

? (a)

0.50 \text{ M}

(b)

0.375 \text{ M}

(c)

0.125 \text{ M}

(d)

0.060 \text{ M}