Number of molecules NH₃ = 4.45 x 10²²
Further explanation
A mole is a number of particles(atoms, molecules, ions) in a substance
This refers to the atomic total of the 12 gr C-12 which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles
Can be formulated :
N = n x No
N = number of particles
n = mol
No = 6.02.10²³ = Avogadro's number
mol of NH₃ = n = 0.074
So the number of molecules :
[tex]\tt N=n\times No\\\\N=0.0740\times 6.02\times 10^{23}\\\\N=4.45\times 10^{22}[/tex]
