One gram of an alloy of aluminium and magnesium when heated with excess of dil. `HCI` forms magnesium chloride, aluminium chloride and hydrogen. The evolved hydrogen collected over mercury at `0^(0)C` has a volume of `1.2` litre at `0.92 atm` pressure. Calculate the composition of the alloy.

Answer

`Al=0.546g,Mg=0.454g`

Explanation

`Al+3HClrarrAlCl_(3)+(3)/(2)H_(2)uarr`
`1.5x+y=0.04925" "...(I)`
`x` mole
`1.5x " "x+27+yxx24=1`
`Mg+2HClrarrMgCl_(2)+H_(2)uarr`
`x xx9+yxx8=0.33" "...(II)`
`y` mole
`% Al =(x xx27)/(1)xx100=54.6%`
`Mg=45.4%`