Question
The number of gram molecules of oxygen in $$6.02 \times {10^{24}}\,CO$$ molecules is
A.
$$10\,g\,{\text{molecules}}$$
B.
$$5\,g\,{\text{molecules}}$$
C.
$$1\,g\,{\text{molecule}}$$
D.
$$0.5\,g\,{\text{molecule}}$$
Answer :
$$5\,g\,{\text{molecules}}$$
Solution :
$$\eqalign{
& 6.023 \times {10^{23}}{\text{molecules of}}\,CO \cr
& = 1\,mole\,{\text{of}}\,CO \cr
& 6.02 \times {10^{24}}\,{\text{molecules of}}\,CO \cr
& = 10\,moles\,{\text{of}}\,CO \cr
& = 10\,g\,\,{\text{atoms}}\,{\text{of}}\,O \cr
& = 5\,g\,\,{\text{molecules of }}{O_2} \cr} $$