Question

calculate the number of atoms and molecules in 124 grams of phosphorus

Answer 1

molecular mass of phosphorus=31g

31grams contains 6.02*10 raised to power23 atoms

1 gram will contain6.02*10 raised to power 23/31 atoms

124 g will contain 6.02 * 10 raised to power 23/31 * 124 atoms

=6.02*10 raised to power 23*4

= 24.08* 10 raised to power 23 atoms

No of molecules will also be same to no of atoms

Hope this helps

Answer 2

let,
m=mass
M=Molar mass
no of particles=N in molecules
Avogadro's constant=N*
mole=n
n=N÷N*(formula)
n=m÷M(formula)
N÷N*=m÷M(formula)
N=m÷M×N*(formula)
N=124×31×6.02×10^23
N=23,140.88×10^23
^ represents its power for example 10^23=ten power twenty three