Answer:
According to avogadro's law, 1 mole of every substance contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles and weighs equal to its molecular mass.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]
[tex]\text{Number of moles}=\frac{\text{Given molecules}}{\text {Avogadros number}}[/tex]
a. moles in 14.08 g of [tex]C_{12}H_{22}O_{11}[/tex] = [tex]\frac{14.08g}{342.3g/mol}=0.04113moles[/tex]
molecules in 14.08 g of [tex]C_{12}H_{22}O_{11}[/tex] = [tex]0.04113\times 6.023\times 10^{23}=0.2477\times 10^{23}[/tex]
b. moles in 17.75 g of NaCl = [tex]\frac{17.75g}{58.5g/mol}=0.3034moles[/tex]
molecules in 17.75 g of [tex]NaCl[/tex] = [tex]0.3034\times 6.023\times 10^{23}=1.827\times 10^{23}[/tex]
formula units 17.75 g of [tex]NaCl[/tex] = [tex]0.3034\times 6.023\times 10^{23}=1.827\times 10^{23}[/tex]
c. moles in 20.06 g of [tex]CuSO_4.5H_2O[/tex]= [tex]\frac{20.06g}{249.68g/mol}=0.08034moles[/tex]
formula units in 20.06 g of [tex]CuSO_4.5H_2O[/tex]= [tex]0.08034\times 6.023\times 10^{23}=0.4839\times 10^{23}[/tex]