Why does a penny become warmer when a hammer strikes it? A 1.50 kg piece of iron at 600°C is submerged in 20.0 kg of water at 25.0°C. Because the iron is hotter, heat will be transferred to the water until they reach equilibrium (i.e. they have the same temperature). What is the final temperature of both the iron and the water? Assume there are no heat losses to the container and environment. Also assume that no water is lost by evaporation.