84g of water at 22'C are mixed with 150 g of ethanol at 88'C. Find the final temperature
24 g of sodium chloride at 25'C are mixed with 272 g of mercury at 50'C. Find the final temperature of the system.
240 g of water at 20'C are mixed with a sample of iron at 500'C. The final temperature of the system is 42'C. Find the mass of the iron sample.