Two students go to play basketball. They notice the ball is flat (it won't bounce). They decide to pump it up with air. After it is pumped with air, will the ball have more, less, or the same amount of mass as before air was added? Choose the correct statement.

A. The ball has more mass after being pumped with air.
B. The ball has less mass after being pumped with air.
C. The ball has the same amount of mass after being pumped with air.
D. Cannot determine unless we measure the mass.

Justify your answer to #2:

D.

Explanation:

We only know the mass of the ball before it was flat. That saying the children could have overpumped it or put it less than they had in the first place. We will never know the answer until we measure the mass of the ball.

the three components of a nucleotide are the nitrogenous base, the phosphate group and the five-carbon sugar.

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.