Question

how many litres of O2 gas at STP is needed to react completely with 27 gram of aluminium​

Answer 1

Answer:

16.8 L

Explanation:

always first write balanced chemical equation

The balanced equation for the given reaction is:

4 Al + 3 O2 --------> 2 Al2O3

4 moles of aluminium reacts with 3 moles of oxygen. So, 1 mole of aluminium reacts with 0.75 moles of oxygen.  (3/4=0.75)

Volume of oxygen used is  

0.75

×

22.4

litres = 16.8 litres.