How much volume of hydrogen is liberated when 0.12g of magnesium reacts with dilute hydrochloric acid ?

Explanation

The balanced chemical equation for the reaction is
`Mg+2HCl rarr MgCl_(2) +H_(2)`
Atomic mass of Mg= 24g `mol^(-1)`
According to the equation
`{:("1 mol of Mg ( 24g) will"),("liberate 1 mol of " H_(2)):}}= 22.4L` at STP
24g of Mg `-= `22.4L of `H_(2) ` at STP
0.12 g of Mg `= ( 22.4)/( 24) xx0.12 g ` of `H_(2)` at STP
= 0.12 L or
= `112cm^(3)` at STP