Question

A student designs an experiment to test substances X, Y, and Z, to determine which one is a catalyst for the reaction: A + B ® C. Only one of the unknown substances is a catalyst, and the others are nonreactive with A, B, or C. When 10 mL of A is added to 10 mL of B, the reaction takes twenty seconds. Bubbles form when the product C is created. The student prepares three test tubes, each containing both reactants A and B. She adds unknowns X, Y, and Z to test tubes 1, 2, and 3, respectively. She then times the reaction in each test tube from the point when the unknown is added until bubbling stops. How can the student identify the catalyst?
A.The test tube that stops bubbling first contains the catalyst.
B.The test tube that produces the most bubbles contains the catalyst.
C.The test tube that bubbles the longest contains the catalyst.
D.The test tube that does not bubble contains the catalyst.

Answer 1

The answer is option A.

The Student identifies the test tube that stops bubbling first contains the catalyst.

Because Catalyst is a substance which increases the rate of reaction, and the reaction shows that when a product is obtained bubbles formed.

When the student added X, Y and Z to the test tubes. The one which is a catalyst fastened the reaction.