Has a definite volume and shape

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?

Imagine that you push on a large rock. at what point does your effort change the rock’s mechanical energy?

Chemistry worksheet - i am not sure what they are asking for exactly?