A 500 gram glass holds 400 grams of liquid water and 75 grams of ice. After 20 minutes the mass of ice is 50 grams. In 1-2 sentences, assuming no evaporation or sublimation has occurred, calculate the mass of the liquid water at this time and explain how this is found.

Answer 1

Initially, there are 400 grams of liquid water and 75 grams of ice, totaling 475 grams of water in its different states. After 20 minutes, with the mass of ice reducing to 50 grams, this means that 25 grams of ice have melted into liquid water; therefore, the total mass of liquid water at this time is 400 grams (initial liquid) + 25 grams (melted ice) = 425 grams.