A rate of a certain chemical reaction is directly proportional to the square of tge concentration of chemical A present and inversely proportional to a concentration of chemical B present. If the concentration of chemical B is increased by 100%, which of the following is clost to the percent change in the concentration of chemical A required to keep the reaction rate unchanged?
1. 100% decrease
2. 50% decrease
3. 40% decrease
4. 40% increase
5. 50% increase
I have no idea what it is about. Thanks for explanation.
GMAT prep - Rate of chemical
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Lets say rate = K * (a^2 / b) - Eq1
Now b is increased by 100%
therefore new
rate = K * (a1^2/2b) - Eq2
where new a is = a1
Eq1 = Eq2
(a^2 / b) = (a1^2/2b)
a1 = Sqrt(2) * a = 1.414a
Clearly a is approx 40% increased!
D is the answer!
OA please?
Now b is increased by 100%
therefore new
rate = K * (a1^2/2b) - Eq2
where new a is = a1
Eq1 = Eq2
(a^2 / b) = (a1^2/2b)
a1 = Sqrt(2) * a = 1.414a
Clearly a is approx 40% increased!
D is the answer!
OA please?