Question

Suppose a boil water notice is sent out advising all residents in the area to boil their water before drinking it or using it for cooking. You need to boil 19.5 L of water using your natrual gas (primarily methane) stove. What volume of natural gas is needed to boil the water if only 10.1% of the heat generated goes towards heating the water. Assume the density of methane is 0.660g/L, the density of water is 1.00 g/mL, and that the water has an initial temperature of 23.2 °C. Enthalpy of formation values can be found in this table. Assume that gaseous water is formed in the combustion of methane. volume of methane:

Answer 1

riven volume = 19.5L = 19500ml Mass of water - 19500 x 1 = 19 500 g Heat required to boil waten = 19.500g xspecific X [Trinas - Timisia = 19 500X 4.18 4 X (100°C- 23:3 ) = 62 57799.6 ] = 162 57-799 kJ) Heat given by combush on = 6257.799. 10:12 = 619580411 K ] " Enthalpy of combustion of methane = 80 g. 5 kJ/mal Moles wed of methane - 61958.411 802.5 - 77.206 - Mass of methane = 77 206 x 16.04 g/mol - 1238 39 6 9 volume of methane - 1838.396 0.660 = (1876:35 7 ) Hy