Answer:
https://youtu.be/3zmeVamEsWI
Explanation:
It is defined as the ratio of moles of one substance to the moles of another substance in a balanced equation. ... Mole ratios are the central step in performing stoichiometry because they allow us to convert moles of one substance to moles of another substance.
For the first one.. the Reactant side is Zn+2HCl produces Zncl2 and H2... and it is balanced too
Answer:
60%
Explanation:
M(NH4NO3) = 2*14 +4*1 +3*16 = 80 g/mol
M(3O) = 3*16 = 48 g/mol
(48/80) *100 % =60% oxygen by mass.