Question

If 10^21 atoms are removed from 200mg of CO2 , then the no. Of moles of CO2 left are?

Answer 1

Initial number of moles = 0.2 g / 44.01 g/mole = 0.0045 moles
We know that,molecules per mole = Avogadro's number = 6.02*10^23 molecule
So,no. of electrons removed=(10^21 molecules) / (6.02*10^23 molecules/mole) = 0.0017
Therefore,
Number of moles remaining = initial number of moles (n1) - number of moles removed
                                             = 0.0045 moles - 0.0017 moles
                                             = 0.0028