Choose the one best answer to each multiple choice question. Write a short answer, using complete sentences, for each Short Answer question. Be sure you have answered every question. When a solid melts to form a liquid it absorbs heat. When a gas condenses to form a liquid it absorbs heat.
Most materials expand when they freeze from a liquid to a solid.
The temperature at which a liquid boils is not affected by air pressure. Because the molecules are moving so fast, gases have strong intermolecular forces acting. The density of a 5 kg chunk of iron is smaller than the density of a 10 kg chunk of iron. If two objects have the same density they must have the same weight. The density of copper is a unique property of copper.