I don’t know if I am right but I think it is symbol for the first one and the second one is formula.
Terms in this set (28) Explain how knowledge of chemistry can be a more informed citizens? Knowledge of chemistry and other sciences can help you evaluate the data presented, arrive at an informed opinion, and take appropriate action.
When a single compound breaks down into two or more compounds or elements in a chemical reaction then it is known as decomposition reaction.
The chemical symbol for sodium carbonate is 
.
The decomposition of sodium carbonate is:
The decomposition of sodium bicarbonate, will result in the formation of sodium oxide, 
and carbon dioxide, 
.
Hence, carbon dioxide, will produce with sodium oxide, on decomposition of .
Answer: Gas , Solid and Liquid
Explanation:
To complete each sentence , One can easily conclude that the various state of matter are in question here.
To further explain better,
(1) Gas molecule is consider to b moving and also move at a faster rate is respect to others.
(2)Solid molecule usual takes a standing still position unless an external pressure acts on it.
(3) Liquid molecule is capable of starting at same location and then move to another location but not at a faster rate compare to gas molecule.
