Question

The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical a present and inversely proportional to the concentration of chemical b present. If the concentration of chemical b is increased by 100 percent, which

Answer 1

Put directly proportional in nominator and inversely proportional in denominator.

RATE=A2BRATE=A2B, (well as it's not the exact fraction it should be multiplied by some constant but we can ignore this in our case).  

We are told that B increased by 100%, hence in denominator we have 2B. We want the rate to be the same. As rate is directly proportional to the SQUARE of A, A should also increase (nominator) by x percent and increase of A in square should be 2. Which means x2=2x2=2 --> x≈1.41x≈1.41, which is approximately 40% increase. R=A2B=(1.4A)22B=2A22BR=A2B=(1.4A)22B=2A22B