Answer:
The number of molecules= 1.33 × 10∧22 molecules
percentage of mercury = 87%
Explanation:
Given data:
mass of dimethyl mercury = 5.10 g
number molecules of dimethyl mercury in 5.10 g = ?
percentage of mercury = ?
Solution:
First of all we will calculate the molar mass of dimethyl mercury.
molar mass of HgC2H6 = 1×200.6 + 2×12 + 6×1 = 230.6 g/mol
we know that,
230.6 g of HgC2H6 = 1 mol = 6.02 × 10∧23 molecules.
so
For the 5.10 g of sample:
5.10 g/230 g/mol = 0.022 moles of HgC2H6
now we will multiply these number of moles with Avogadro number to get number of molecules in 5.10 g of sample.
0.022 × 6.02 × 10∧23 molecules = 0.133 × 10∧23 molecules or
1.33 × 10∧22 molecules.
Percentage of mercury:
Formula:
percentage = (atomic number of Hg × total number of atoms of Hg/ molar mass of HgC2H6) × 100
% age of Hg = (200.6 g/mol× 1/ 230.6 g/mol) × 100
%age of Hg = 0.869 × 100
%age of Hg = 86.99 % or 87 %
