How many kilojoules of heat are released when 38.1 g of [tex]CH_4(g)[/tex] reacts completely with [tex]O_2(g)[/tex] to form [tex]CH_3OH(g)[/tex] at constant pressure?

To calculate the heat released when 38.1 g of methane burns, we find the number of moles and then multiply by the heat released per mole. The combustion of 1 mole of methane releases 890.4 kJ, so for 38.1 g (2.375 moles), the heat released is approximately 2115.45 kJ.

The question asks about the amount of heat released when 38.1 g of methane (CH4) reacts with oxygen (O2) to form methanol (CH3OH). We're given that the combustion of 1 mole of methane releases 890.4 kJ of heat. To find the answer, we need to calculate the number of moles in 38.1 g of methane and then use that to determine how much heat is released.

To calculate the number of moles of methane, we use the molar mass of methane, which is approximately 16.04 g/mol:

Moles of CH4 = 38.1 g / 16.04 g/mol ≈ 2.375 moles

Now, to find the heat released, we multiply the number of moles by the heat released per mole:

Heat released = 2.375 moles \\times 890.4 kJ/mol ≈ 2115.45 kJ

Therefore, when 38.1 g of methane is combusted, approximately 2115.45 kJ of heat is released.