Question

1.0 g of magnesium is burnt with 0.56 g O2 in a closed vessel. Which reactant is left in excess and howmuch ?

Answer 1

47.16g of Mg is left.
0.56g of O2 reacts with 0.84g og Mg.
So, 47.16g of Mg left unreactive.

Answer 2

Answer:

0.16 g of Mg

Explanation:

since O2 is limiting reagent then as in the reaction -

2Mg+O2 - 2MgO

32g of 02 reacts with 48g of Mg and

1g of O2 will need 48/32g of Mg

and 0.56g of O2 will need 48/32 ×0.56 =0.84 g of Mg

then when subtracted from 1 g of magnesium the amount of residue of mg will be 0.16g