Question

how are 0.50 mol Na2Co3 and 0.50 Na2Co3 different

Answer 1

1 mol=6.022×10^23 molecule.

therefore 0.50 mol Na2Co3 is 6.022×10^23 molecules and 0.50 Na2Co3 is half atom of its molemule

Answer 2

mole :
It is amount of the substance which has 6.022×10^23 particles
or It is a if substance which has same number of molecules as their in 12 g of carbon-12 isotope.
1 mol = 6.022 × 10^23 molecules

molar mass of Na2CO3
= (23×2)+12+(3×16)
= 46+12+48
= 106 g/mol

mass = number of moles × molar mass
mass = 0.50mol × 106g/mol
mass = 53 g

volume = number of moles × 22.7 l
volume = 0.50 × 22.7 l
volume = 11.35 l

molecules = number of moles × 6.022×10^23
molecules = 0.50×6.022×10^23 molecules
molecules = 3.011 molecules

atoms = number of moles × atomicity × 6.022×10^23 atoms
atoms = 0.50 × 6 × 6.022 × 10^23 atoms
atoms = 18.066 atoms

_____________________________________see attachment tell me what 0.50 it's unit gram or mol in comments