Water with a mass of 186 g at t 373 K was added water at t 283 K and a mixture of t 300 K was obtained

Water with a mass of 186 g at t 373 K was added water at t 283 K and a mixture of t 300 K was obtained. The mass of added water is

To find out the mass of added water, consider the equality: Cw * mx * (t – tx0) = Cw * mk * (tk – t), whence we express: mx = Cw * mk * (tk – t) / (Cw * (t – tx0)) = mk * (tk – t) / (t – tx0).

Data: mk – the mass of boiling water (mk = 186 g); tк – boiling water temperature (tк = 373 К); t is the temperature of the resulting mixture (t = 300 K); tx0 is the initial temperature of cold water (tx0 = 283 K).

Let us perform the calculation: mх = mk * (tk – t) / (t – tx0) = 186 * (373 – 300) / (300 – 283) = 798.7 g.

Answer: Cold water weighing 798.7 g should have been added to the boiling water.