Answer:
Deposition is the phase transition in which gas transforms into solid
Explanation:
The amount of energy in molecules of matter determines the state of matter. Matter can exist in one of several different states, including a gas, liquid, or solid state. ... A gas is a state of matter in which atoms or molecules have enough energy to move freely.
A covalent bond is a form of chemical bonding between two non-metals, whereas ionic bonding is a bond between a metal and a non-metal.
<u>Answer:</u> The chemical reaction for the synthesis reaction is given below.
<u>Explanation:</u>
Synthesis reaction is defined as a chemical reaction in which two small chemical substances combine together to form a single compound. The general equation for this chemical reaction follows:

For the reaction of calcium and oxygen combining together to form calcium oxide, the equation follows:

By Stoichiometry,
2 moles of calcium element combines together with 1 mole of oxygen gas to produce 2 moles of calcium oxide.
Hence, the chemical equation for the reaction is given above.
It says it will never change. So whatever it was before the change, it will be the same after the change. So, 200 should be correct.