Answer:
When a gas is heated, the molecules move faster, bump into each other, and spread apart. Because the molecules are spread apart, they take up more space. They are less dense.
Answer:
They are called homogenous mixtures. If you put sand into a glass of water, it is considered to be a mixture. You can always tell a mixture, because each of the substances can be separated from the group in different physical ways. You can always get the sand out of the water by filtering the water away.
The Second Law of Thermodynamics<span> says that processes that involve the transfer or conversion of heat energy are irreversible.</span><span> ... The First </span>Law of Thermodynamics<span> states that energy cannot be created or destroyed; the total quantity of energy in the universe stays the same.</span>
It gains or loses electrons to become like the Noble gases having 8 valence electrons to become the most stable.
