Question

The reaction between aluminium carbide and water takes place according to thefollowing equation:

Al4C3 + 12 H2O 3CH4 + 4Al(OH)3

Calculate the volume of methane measured at STP, released from 14.4 g of aluminium carbide by excess water.

Answer 1

According to balance equation 
Al4C3 + 12 H2O → 3CH4 + 4Al(OH)3
Molar mass of aluminium carbide is 144 g mol-1
Number of moles of Aluminium carbide = 12 g/ 144 g mol-1
​                                                                       = 1/12 mol
​1 mol of aluminium carbide produce 3 moles of methane at STP.
1 mole = 22.4 L at STP
Therefore 3 mole = 3 x 22.4 L  = 67.2 L of methane at STP​
Or 1 mole of Aluminium carbide produce 67.2 L of methane at STP
therefore 1/12 mol of Aluminium carbide will produce = 67.2 L/1 mol x 1/12 mol
                                                                                   = 5.6 L of methane

Answer 2

Aluminum carbide react with water to produce aluminium hydroxide and methane. Chemical reaction. Balancing chemical equations. ... Al4 C3 + 12H2O → 4Al(OH)3 + 3CH4.