What is the name of the element with the atomic number 79

Why is nh3 classified as a polar molecule

Adepositional also feature that forms where a stream enters a lake or an ocean is a

A5 mole sample of liquid acetone is converted to a gas at 75.0°c. if 628 j are required to raise the temperature of the liquid to the boiling point, 15.600 kj are required to evaporate the liquid, and 712 j are required to raise the final temperature to 75.0°c, what is the total energy required for the conversion?