Answer: The partial pressure of oxygen is 187 torr.
Explanation:
According to Raoult's law, the partial pressure of a component at a given temperature is equal to the mole fraction of that component multiplied by the total pressure.
where, x = mole fraction
= total pressure
,
,
Thus the partial pressure of oxygen is 187 torr.
The oxidation state of the atoms of any molecule in the element state equals zero. H2 is is the element state, therefore the oxidation state of the whole molecule equals zero and the oxidation states of the atoms also equals zero. Answer letter D is the correct answer.
Magnesium has an oxidation state = zero before it undergoes the reaction and is oxidized. The oxidations state of the magnesium in Mg(OH)2 is +2.