Hi!
I'm not entirely sure about this so I'm sorry if I'm wrong but I think it would be helium.
Again in not entirely sure but i hope this helped you, i hope you have a great day, afternoon, or night!
Answer: The green copper (II) carbonate
changes to black copper oxide 

Explanation:
Decomposition is defined as the chemical reaction in which a single compound gives two or more simple substances. It requires energy to break the bonds between reactants, thus is an endothermic process.
Thermal decomposition uses heat for decomposition.
The chemical equation for thermal decomposition of copper (II) carbonate is:

The green copper (II) carbonate
changes to black copper oxide 
Answer:
97 000 g Na
Explanation:
The absortion (or liberation) of energy in form of heat is expressed by:
q=m*Cp*ΔT
The information we have:
q=1.30MJ= 1.30*10^6 J
ΔT = 10.0°C = 10.0 K (ΔT is the same in °C than in K)
Cp=30.8 J/(K mol Na)
If you notice, the Cp in the question is in relation with mol of Na. Before using the q equation, we can find the Cp in relation to the grams of Na.
To do so, we use the molar mass of Na= 22.99g/mol

Now, we are able to solve for m:
=97 000 g Na
Answer: Atomic number, atomic mass, and relative atomic mass
Explanation: