Question

a researcher is designing a laboratory experiment to determine whether the inorganic substance a affects the rate of reaction between two colored liquids, x and y. when the reaction is complete, the liquid is clear. the reaction between x and y is similar to one used by manufacturers to produce certain chemicals in factories. which method would be best answer his question about reaction rate and what will he find out about substance a? first, he should measure the final temperature of the liquid when x and y react without substance a. then, he should measure how long it takes for the liquid to become clear if x and y are mixed together. then, he should measure how long it takes if he also adds substance a to x and y. he will find out if substance a is a catalyst. first, he should measure the final temperature when he adds substance a to x and y. he will find out if substance a is an enzyme.

Explanation:

Step1: Identify the goal

The goal is to determine the reaction rate and effects of substance A on the reaction between X and Y. Measuring the time it takes for the liquid to become clear indicates the completion of the reaction and can be used to calculate the reaction rate.

Step2: Analyze the options

Measuring the final temperature is not directly related to the reaction rate or the role of substance A in the reaction. Measuring time for clarity is a valid way to assess reaction progress.

Step3: Select the best method

The best way to find out about the reaction rate and the effect of substance A is to measure how long it takes for the liquid to become clear when X and Y are mixed and when substance A is added.

Answer:

First, he should measure how long it takes for the liquid to become clear if X and Y are mixed together. Then, he should measure how long it takes if he also adds substance A to X and Y. He will find out if substance A is an enzyme.