Answer: The mass of chlorine gas required is 94.6 mg
Explanation:
The number of moles is defined as the ratio of the mass of a substance to its molar mass.
The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)
Given mass of gold = 0.175 g
Molar mass of gold = 197 g/mol
Plugging values in equation 1:
[tex]\text{Moles of gold}=\frac{0.175g}{197g/mol}=0.000888 mol[/tex]
The given chemical equation follows:
[tex]2Au+3Cl_2\rightarrow 2AuCl_3[/tex]
By the stoichiometry of the reaction:
If 2 moles of gold reacts with 3 moles of chlorine gas
So, 0.000888 moles of gold will react with = of chlorine gas
Molar mass of chlorine gas = 71 g/mol
Plugging values in equation 1:
[tex]\text{Mass of chlorine gas}=(0.001332mol\times 71g/mol)=0.0946g=94.6mg[/tex] (Conversion factor: 1 g = 1000 mg)
Hence, the mass of chlorine gas required is 94.6 mg