Question

if 1.5 moles of oxygen combine with Al to form Al2O3 , the mass of Al in gram used in this reaction (atomic mass of Al =27)​

Answer 1

Answer:

4Al + 3O2 ---> 2Al2O3

1mole O2 = 32g * 1.5mole = 48g * 2 = 96g

Al2O3 = 101.96g/mole * 2 = 203.92g

203.92g - 96g O2 = 107.92g.

Therefore,

The weight of Al in the reaction of 1.5moles of O2 is 107.92g

Answer 2

Answer: 40.5 g of Al

Explanation:

2Al + 3 O2 --->2 Al2O3

1 mole = 27 gm of Al

1.5 mole = x gm of Al

x = 1.5 × 27

= 40.5 gm

Hence mass of Al used is 40.5 g .