What mass of natural gas (ch4) must you burn to emit 264 kj of heat?
ch4(g)+2o2(g)→co2(g)+2h2o(g)δh∘rxn= −802.3kj

The heat released by cpmolete the combustion of organic products with oxygen is called heat of combustion.

Here 1 mol of CH4 realesed 802.3 KJ

To emit 264 kJ you multiply you need (1 mol of CH4/802.3 kJ)* 264 kJ = 0.329 mol of CH4

The molar mass, MM, of CH4 is 12 g/mol + 4*1g/mol = 16 g/mol

The to obtain the mass multiply the number of moles times the molar mass:

mass = n * MM = 0.329mol * 16g/mol = 5.26 grams

5.26 grams

Although the diagram is not shown, i know that the convection is heated by a the core.