Which of the following contain same number of carbon atoms as in 6 g of carbon-12?

Options

A. 7.5 g ethane
B. 8 g methane
C. both (a) and (b)
D. none of these

Answer

C

Explanation

No. of moles of carbon present in 6 g of C-12 = Mass / Molar mass
= 6/12 = 0.5 moles = `0.5 xx 6.022 xx 10^(23)` carbon atoms.
No. of moles in 8 g of methane = 8 /16 = 0.5 moles
` = 0.5 xx 6.022 xx 10^(23)` carbon atoms.
No. of moles in 7.5 g of ethane = 7.5 / 16 - 0.25 moles = `2 xx 0.25 xx 6.022 xx 10^(23)` carbon atoms