Answer:
3 atoms of (C)carbon, 5 atoms of (H)hydrogen and 2 atoms of (O)oxygen
Explanation:
i don't know what you mean by subscribe
and i don't know what a coefficient is
In order to find the density of an object, you need to know the mass of the object and the volume.
That is why the unit of density is kg/m3.
Hope it helps
Answer: Lithium
Explanation: The balanced chemical equation is:

It can be seen, 4 moles of lithium combines with 1 mole of oxygen gas to produce 2 moles of lithium oxide.
Thus 8.4 moles of lithium combines with=
of oxygen gas to produce 4.2 moles of lithium oxide.
As, Lithium limits the formation of product, it is the limiting reagent and Oxygen gas is present in excess, it is called the excess reagent. (4.6-2.1)=2.5 moles of oxygen gas are present in excess.