\(2.8\times {10}^{-3}\mathrm{mol}\mathrm{of}{\mathrm{CO}}_{2}\)is left after removing \({10}^{21}\)molecules from its ' …

\(2.8\times {10}^{-3}\mathrm{mol}\mathrm{of}{\mathrm{CO}}_{2}\)is left after removing \({10}^{21}\)molecules from its ' x ' mg sample. The mass of \({\mathrm{CO}}_{2}\) taken initially is

(Given : \({\mathrm{N}}_{\mathrm{A}}=6.02\times {10}^{23}{\mathrm{mol}}^{-1}\))