5.6L of O2 means we have 0.25 moles of O2.
As, 1 mole has 6.023*10^23 molecules,
0.25 moles of O2 will have 0.25*6.023*10^23 molecules=1.50575*10^23 molecules
and as 1 molecule of O2 has 2 atoms, so, 1.50575*10^23 molecules will have 2*1.50575*10^23 atoms=3.0115*10^23 atoms of O.
First there is a need to calculate the molar mass of Ba(NO₃)₂:
137.3 + 2 (14.0) + 6 (16) = 261.3 grams/mole
The molar mass, denoted by M in chemistry refers to a physical characteristic illustrated as the mass of a given component divided by the amount of the component. The molar masses are always denoted in grams/mole.
After finding the molar mass, the number of moles can be identified as:
432 grams / 261.3 g/mol = 1.65 moles of Ba(NO₃)₂.
I’ll do the first two for you.
