. A fifth-grade student was showing her little brother what she was learning in science class. She mixed 20 grams (g) of a white powder in 80 milliliters (mL) of warm water. What is the weight (mass) of the white powder and water mixture?

3. how much energy in joules is required to evaporate .0005 kg of liquid ammonia to vapor at the same temperature? 4. how much energy ( in megajoules ) is given up by .75 kg of water at 0c when it freezes to form ice at 0c? 5. explain how heat works between and at critical temperatures?