Question

Question #f9e09

Answer 1

The correct choice is A.

Explanation:

Check the equation. It states that each one mole of `CH_4` produces 3 moles of `H_2`.

So, the `H_2` is produced at three times the rate of `CH_4`.

Also, `CH_4` is used up, so its concentration decreases - a negative change. `H_2` on the other hand is produced, so its concentration rises - a positive change.

Taken together these two differences make "A" the correct choice.

Answer 2

B. `-(DeltaCH_4)/(Deltat) = 3(Delta H_2)/(Deltat)`

Explanation:

The "rate" for the reaction must be the same for all components. Thus, the "rate of change" of one compound to another will be the ratio of their balanced molar amounts in the equation.

This equation shows that for every mole of methane "reacted", three moles of hydrogen are formed. Thus, the relative rate of change of methane to hydrogen is `1/3`, and in the opposite direction, (-). This is shown as answer B., where the ratio (3) is put on the other side of the equation.

`-(DeltaCH_4)/(Deltat) = 3(Delta H_2)/(Deltat)`