4hcl + o2 ⇌ 2h2o + cl2

which of the following would result from increasing the volume of oxygen?
the volume of hydrochloric acid increases.
the rate of forward reaction increases.
the rate of backward reaction increases.
the volume of water vapor decreases.

The rate of forward reaction increases.

Explanation:

Increasing the volume of oxygen:

will increase the concentration of oxygen (reactants), so the equilibrium will be shifted to the right side (products side) to suppress the effect of increasing the volume of oxygen.

So, the right choice is: The rate of forward reaction increases.

the ratio of the conjugate base to the acid required to attain the desired ph.