Convection is cool things sinking and hot things rising. So for example when you have the heat on the upstairs is always hotter than downstairs because heat rises and continues to go in circles until the whole house it heated up.
A Trombe wall (Trombe rhymes with prom, by the way) is a wall that warms trapped air, and then circulates it to help heat a house. Trombe walls are ideally made out of a material with a fairly high thermal mass materials (like bricks or concrete), and are often painted black to improve heat conduction
Vary in the number of neutrons but Sama in the number if protons are called isotopes
Answer:
don't know this one sorry