How many kilograms of centigrade steam is required to heat a 200 kg concrete slab from 10 to 40 ℃?

To find the mass of the spent centigrade steam, we use the equality: Cb * m1 * (t – t0) = L * m2, whence m2 = Cb * m1 * (t – t0) / L.

Values of variables and constants: Cb – beats. heat capacity of heavy concrete (Sb ≈ 1000 J / (kg * K)); m1 is the mass of the concrete slab (m1 = 200 kg); t – end. plate temperature (t = 40 ºС); t0 – early. temperature (t0 = 10 ºС); L is the heat of vaporization of water (L = 2.3 * 10 ^ 6 J / kg).

Calculation: m2 = Cb * m1 * (t – t0) / L = 1000 * 200 * (40 – 10) / (2.3 * 10 ^ 6) = 2.61 kg.