Answer:
Relative molecular of the compound or infomation like vapour density, volume occupied by a known mass of its vapour at stp, etc
Explanation:
The molecular mass of a compound is twice its vapour density. We can find the molecular formula using the relationship below:
- Empirical formula is the simplest formula of a compound. It repeats itself "n" times to become a molecular formula i.e (EF)ₙ = MF...... n is the number of times the empirical formula presents in a mole of the compound.
- Most times, n is a whole number like 1,2,3,.....
Answer:
The answer to your question is -2855 J
Explanation:
Reaction
2C₂H₆ + 7O₂ ⇒ 4CO₂ + 6H₂O
Formula
Heat of reaction = ΔHrxn = ΣΔHrxn products - ΣΔHrxn reactants
Substitution
ΔHrxn = { 4(-393.5) + 6(-241.8)} - {2(-84.7) + 7(0)}
ΔHrxn = {-1574 -1450.8} - {-169.4}
ΔHrxn = -3024.8 + 169.4
ΔHrxn = -2855.4 J
If you have a magnesium for every oxygen, then you have to start with two magnesiums. So the balanced equation is 2 Mg + O2 2 MgO.
And
CaCO3———→CaO + CO2
I hope it helped!
The carbon is considered because it is form by oxygen atoms