Hi guys, my question is: Bromoethane is converted to methanol in an alkaline solution. This reaction is first order with respect to each reactant. CH3Br(aq) + NaOH(aq) --> CH3OH(aq) + NaBr(aq) a) What is the rate law for this reaction? b) Predict how the reaction rate will change when the concentration of NaOH is decreased by a factor of 5. c) Predict the change in reaction rate when the concentrations of both reactant are doubled?

Chemistry · Middle School · Thu Feb 04 2021

Answered on

 a) The rate law for this reaction can be expressed based on the order with respect to the reactants. Since the reaction is first-order with respect to each reactant (bromoethane, CH3Br, and sodium hydroxide, NaOH), the rate law will reflect this. The rate law is given by:

Rate = k [CH3Br][NaOH]

where: - Rate is the rate of the reaction. - k is the rate constant for the reaction. - [CH3Br] is the molar concentration of bromoethane. - [NaOH] is the molar concentration of sodium hydroxide.

b) If the concentration of NaOH is decreased by a factor of 5, the reaction rate will also decrease by a factor of 5. This is because the rate is directly proportional to the concentration of NaOH, as seen in the rate law. So if [NaOH] is reduced by 5 times, the rate becomes 1/5 of the original rate.

c) When the concentrations of both reactants are doubled, the rate of the reaction will change by a factor determined by the individual rate changes in each reactant. Since both reactants are first-order:

- Doubling [CH3Br] will increase the reaction rate by a factor of 2. - Doubling [NaOH] will also increase the reaction rate by a factor of 2.

Therefore, doubling both [CH3Br] and [NaOH] will increase the reaction rate by a factor of 2 * 2, which is 4. So the reaction rate will be four times faster when the concentrations of both reactants are doubled.