Question

Aluminium reacts with oxygen to give aluminium oxide. How many moles of oxygen required to react completely with 0.5 moles of aluminium?

Answer 1

ANSWER

As reaction for the formation of Al2O3 is as follows:

4Al+3O2→Al2O3

this shows that 4 mol reacts to 3 mol ( 96 g) of O2

so as 3 mol O2 to 4 mol Al

then 0.5 mol O2 to 34×0.5=0.66 mol of Al

as 1 mol Al = 27 g

then 0.66 mol of Al=0.66×27=17.9 g≈18 g 

Hence, the correct option is B

Answer 2

Step-by-step explanation:

5 moles of oxygen combine with aluminium to form Al2O3, then the weight of aluminium metal used in the reaction is: [atomic weight of Al=27 amu]