Question

The table shows the rate of reaction for two unknown time intervals during a chemical change. Reaction Rates Time Intervals (s) Rate (M/s) T1 1.8 × 10−6 T2 1.0 × 10−6 Which of the following is true for the two time intervals? T1 is longer than T2, and the concentration of reactants at the end of T1 is lower than that of T2. T1 is longer than T2, and the concentration of products at the end of T1 is lower than that of T2. T1 is shorter than T2, and the concentration of reactants at the end of T1 is higher than that of T2. T1 is shorter than T2, and the concentration of products at the end T1 is higher than that of T2.

Answer 1

T1 is shorter than T2, and the concentration of products at the end T1 is higher than that of T2.

Step-by-step explanation:

• The rate of the reaction is defined as the change in the concentration of reactants (decrease) or products (increase) with time.

Rate of the reaction = - d[reactants]/dt = d[products]/dt

• It is clear that the rate of the reaction is inversely proportional with time.

∵ Rate at T1 (1.8 x 10⁻⁶ M/s) > rate at T2 (1.0 x 10⁻⁶).

∴ T1 < T2, which means that T1 is shorter than T2.

• Also, it is clear that the rate of the reaction is directly proportional to the change of reactants.

As, the rate increases, the remaining of the reactants decrease and products formed increase.

So, concentration of reactants at the end of T1 is lower than that of T2 and the concentration of products at the end T1 is higher than that of T2.

• So, the right choice is:

T1 is shorter than T2, and the concentration of products at the end T1 is higher than that of T2.