Question

3/2/2016 An unknown substance at a temperature of 20 degrees Celsius is warmed up to 50 degrees when water at 80 degrees is added to it. The sum of the masses of the unknown substance and water is equal to 1000grams. In another experiment, the same substance at 20 degrees is warmed up to 52 degrees when the mass of the substance is 70 grams less than the original mass and water (same mass) at 80 degrees is added to it (masses add up to 930 grams). Find the specific heat of the unknown substance.

Answer 1

let u be the mass of the unknown substance of specific heat H.

uH(50-20)+(1000-u)cwater*(50-80)=0
after that, third sentence, makes no sense to me.