Question

What volume of H2 is evolved at STP when 2.7 g aluminium reacts completely with aqueous NaOH

Answer 1

2 Al + 2 NaOH + 2 H2O = 2 NaAlO2 + 3 H2

Al = 27

2x27 = 54 g



54g of Al produce 3 moles H2

2.7g produce = (2.7x3)/54

                      = 0.15 moles of H2


Molar volume of gas at STP = 22.4 Litres


0.15 moles will have a volume of = 0.15 x 22.4

                                                      = 3.36 litres

Answer 2

Answer:

Explanation:

2 Al + 2 NaOH + 2 H2O = 2 NaAlO2 + 3 H2

Al = 27

2x27 = 54 g

54g of Al produce 3 moles H2

2.7g produce = (2.7x3)/54

= 0.15 moles of H2

Molar volume of gas at STP = 22.4 Litres

0.15 moles will have a volume of = 0.15 x 22.4

= 3.36 litres