Answer: The number of formula units in the given amount of NaCl are [tex]1.1\times 10^{18}[/tex]
Explanation:
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]
Given mass of NaCl = 0.11 mg = [tex]1.1\times 10^{-4}g[/tex] (Conversion factor: 1 g = 1000 mg)
Molar mass of NaCl = 58.5 g/mol
Putting values in above equation, we get:
[tex]\text{Moles of NaCl}=\frac{1.1\times 10^{-4}g}{58.5g/mol}=1.88\times 10^{-6}mol[/tex]
According to mole concept:
1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of formula units
So, [tex]1.88\times 10^{-6}mol[/tex] moles of NaCl will contain = [tex](1.88\times 10^{-6}\times 6.022\times 10^{23})=1.1\times 10^{18}[/tex] number of formula units
Hence, the number of formula units in the given amount of NaCl are [tex]1.1\times 10^{18}[/tex]
