Question

A student is observing the reaction between hydrochloric acid and zinc metal. When 10 M HCl is used instead of 10 M HCl, the student observes an increased bubbling. This is a result of an increase in _____. (1 point)
(A) the energy of the reactant molecules

(B) activation energy of the reaction

(C) the surface area of the zinc metal

(D) collisions between reactant molecules

Answer 1

"When 10 M HCl is used instead of 10 M HCl, ..."
Is one of these a typo? It is difficult to note a change when we replace it with the same thing.

Answer 2

No, that's the question. No typo

Answer 3

Then there is no more to the question either?

I am left to assume that these numbers were meant to be different, but the author of the question mistakenly used 10 M on both, unless there is just some missing information written elsewhere, like a temperature change or the like.

The reaction we are looking at has skeletal eqn: Zn + HCl to ZnCl2 + H2 <-- Hydrogen gas is bubbling out.
If we assume the amount of HCl used is increasing in concentration (10 M HCl to say, 15 M HCl), then the amount of particle collisions is increasing because more of the HCl is there to bump into Zn particles.

Answer 4

no, no more to the question either. thank you though

Answer 5

Glad to help!