Answer :
Answer: 1. The empirical formula is [tex]PNF_2[/tex]
2. The molecular formula is [tex]PNF_2[/tex]
Explanation:
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mass of P = 37.32 g
Mass of N = 16.88 g
Mass of F = 45.79 g
Step 1 : convert given masses into moles.
Moles of P =[tex]\frac{\text{ given mass of P}}{\text{ molar mass of P}}= \frac{37.32g}{31g/mole}=1.20moles[/tex]
Moles of N =[tex]\frac{\text{ given mass of N}}{\text{ molar mass of N}}= \frac{16.88g}{14g/mole}=1.20moles[/tex]
Moles of F =[tex]\frac{\text{ given mass of F}}{\text{ molar mass of F}}= \frac{45.79g}{19g/mole}=2.41moles[/tex]
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For P = [tex]\frac{1.20}{1.20}=1[/tex]
For N = [tex]\frac{1.20}{1.20}=1[/tex]
For F =[tex]\frac{2.41}{1.20}=2[/tex]
The ratio of P: N: F= 1: 1: 2
Hence the empirical formula is [tex]PNF_2[/tex]
The empirical weight of [tex]PNF_2[/tex]= 1(31)+1(14)+2(19)= 82.98 g.
The molecular weight = 82.98 g/mole
Now we have to calculate the molecular formula.
[tex]n=\frac{\text{Molecular weight}}{\text{Equivalent weight}}=\frac{82.98}{82.98}=1[/tex]
The molecular formula will be=[tex]1\times PNF_2=PNF_2[/tex]