Aswimming pool, 10.0 m by 4.0 m, is filled with water to a depth of 3.0 m at a temperature of 20.2°c. if the energy needed to raise the temperature of the water to 29.7°c is obtained from the combustion of methane (ch4), what volume of methane, measured at stp, must be burned? ∆hcombustion for ch4 = -891 kj/mol

119.69 kilo liter volume of methane measured at STP, must be burned.

Explanation:

Length of the pool= 10.0 m

Breadth of the pool = 4.0 m

Height upto which the pool will be filled= 3.0 m

Volume of the water in the pool = volume of the pool :

= 10.0 m × 4.0 m × 3.0 m =

Density water =

Mass of the water(m) =

Energy required to raise the temperature = Q

Mass of the water = m = 119,640 kg =

Specific heat of water ,c= 4.186 J/g °C

Change in temperature,

Heat required to raised the temperature is 476,1133.6 kJ.

Heat evolved when 1 mol of methane = -891 Kj

Number of moles of methane giving (- 476,1133.6) kJ of heat:

At STP, 1 mol occupies = 22.4 L

Then 5,343.58 mol will occupy :

119.69 kilo liter volume of methane measured at STP, must be burned.