Consider the reaction, C2H4(g) + H2(g) - C2H6(8), where AH = -137 kJ. How many kilojoules are released when 3.5 mol of CH4 reacts?
480 kJ are released
20 x 103 kJ are released
570 kJ are released
137 kJ are released​

480 kJ of energy is released when 3.5 mol of reacts.

Explanation:

The balanced chemical reaction is:

Thus it is given that the reaction is exothermic (heat energy is released) as enthalpy change for the reaction is negative.

1 mole of on reacting gives = 137 kJ of energy

Thus 3.5 moles  of on reacting gives = of energy

Thus 480 kJ of energy is released when 3.5 mol of reacts.

fdvwsa gfwsargebgeebbfwfwffw gwf   vgwgw gw f gwgw fgw v v dsv dwfff