Question

From 200mg of Co2 when X molecules are removed, 2.89*10-3 moles of CO2 are left. X will be

Answer 1

Answer:

Explanation:

2

Answer 2

Answer:  10^21 molecules of CO2

Explanation:  We have 200 mg of carbon dioxide. The molar mass of carbon dioxide is 44g. That is there are 6.022 × 10^23 molecule of CO2 in 44g of CO2.

Thus, number of moles of CO2 in 44g of CO2 = 1  

number of moles of CO2 in 1g of CO2 = 1 / 44  

number of moles of CO2 in 200 mg or 200 × 10^-3 g of CO2  

= (1 × 200 × 10^-3) / 44  

= 4.545 × 10^-3 moles  

We are given that after removing X molecules from 200 mg of CO2, 2.89 X 10^-3 moles of CO2 are left.

Therefore, number of moles of CO2 removed will be  

= total number of moles of CO2 - number of moles of CO2 left  

= 4.545 × 10^-3 - 2.89 × 10^-3  

= 1.655 × 10^-3 moles of CO2  

Thus, 1.655 × 10^-3 moles of CO2 were removed. The number of molecules X can be calculated by simply multiplying this quantity with Avogadro's number.  

So, number of CO2molecules removed will be  

= 1.655 X 10^-3 X 6.022 X 10^23  

= 9.969 X 10^20 molecules of CO2

=10 X 10^20 molecules of CO2

=10^21 molecules of CO2