Answer:
The correct answer is option (a).
Explanation:
The molecular formula of lithium carbonate is [tex]Li_2CO_3[/tex]
Percentage of lithium in lithium carbonate = 18.8 %
Molar mass of the lithium carbonate = M
Atomic mass of lithium = 7 g/mol
[tex]18.8\%=\frac{2\times 7 g/mol}{M}\times 100[/tex]
M = 74.46 g\mol
Mass of pure lithium carbonate is twice the mass of first sample:[tex]2\times 74.46 g/mol =148.92 g/mol[/tex]
Percentage of lithium in pure lithium carbonate sample:
[tex]\%=\frac{2\times 7 g/mol}{148.92 g/mol}\times 100=9.40\%[/tex]
The correct answer is option (a).
