Given mass of CO2 = 200 mg = 0.2 g
Molar mass of CO2 = 44 g/mol
Number of moles of 200 mg CO2 = Given mass/Molar mass of CO2
= 0.2 g/44 g mol-1 = 0.00454 mole
Number of molecules of CO2 removed = 1021
Number of moles of CO2 removed = 1021/(6.022*1023) = 0.00166 mole
Number of moles of CO2 left = 0.00454 – 0.00166 = 0.00288 mole
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