How many times more heat will be released with the complete combustion of hydrogen with a mass of 5 KG

How many times more heat will be released with the complete combustion of hydrogen with a mass of 5 KG than with the complete combustion of dry birch yards of the same mass?

Given:

m1 = m2 = m = 5 kilograms – the mass of hydrogen and birch firewood;

q1 = 12 * 10 ^ 7 J / kg – specific heat of combustion of hydrogen;

q2 = 1.0 * 10 ^ 7 J / kg is the specific heat of combustion of birch firewood.

It is required to determine Q1 / Q2 – how many times more heat will be released during the combustion of hydrogen than during the combustion of birch firewood.

When hydrogen burns, heat will be released, equal to:

Q1 = q1 * m1 = q1 * m.

When birch firewood is burned, heat will be released, equal to:

Q2 = q2 * m2 = q2 * m.

Then:

Q1 / Q2 = q1 * m / (q2 * m) = q1 / q2 = 12 * 10 ^ 7 / (1.0 * 10 ^ 7) = 12/1 = 12 times.

Answer: when hydrogen burns, 12 times more heat will be released than when birch firewood is burned.