Step-by-step explanation:
The reaction of magnesium with HCl is as follows -
Mg + HCl ----> MgCl₂ + H₂
The reaction of magnesium with HCl is as follows -
Mg + H₂O ----> Mg ( OH )₂ + H₂
In the above two reactions , hydrogen gas is evolved in both the cases , but in the first reaction , the hydrogen gas is of higher concentration , but in the second reaction the evolved hydrogen is very less , since , the magnesium hydroxide produces will form a protective layer around the magnesium and will prevent the reaction .
and
hence in both the case , the hydrogen produced will be different .