What mass of kerosene must be burned in order to heat water with a mass of 3 kg per 100 C?

What mass of kerosene must be burned in order to heat water with a mass of 3 kg per 100 C? Specific heat of water с = 4200 J / kg × С

These tasks: m1 (mass of heated water) = 3 kg; Δt (change in water temperature) = 100 ºС.

Reference values: q (specific heat of combustion of kerosene) = 46 * 10 ^ 6 J / kg; by the condition of the problem C (specific heat capacity of water) = 4200 J / (kg * K).

We determine the mass of kerosene burned from the equality: C * m1 * Δt = q * m2; m2 = C * m1 * Δt / q.

Let’s make calculations: m2 = 4200 * 3 * 100 / (46 * 10 ^ 6) ≈ 0.027 kg or 27 g.

Answer: To heat 3 kg of water at 100 ºС, you need to burn 27 g of kerosene.