Question

if 10 power 21 molecules are removed form 200mg of CO2 then the number of moles of CO2 left are : ​

Answer 1

Answer:

$\tt 2.89\times 10^-^3 mol$

Explanation:

Given Problem:

if 10 power 21 molecules are removed form 200mg of CO2 then the number of moles of CO2 left are?

Solution:

Given that,

$\sf Molar\;mass\; of\; CO_2 = 44g/mol\\\\\ Amount\;of\;CO_2\; taken\;= \dfrac{0.2g}{g}\\\ 44\dfrac{g}{mol}\\\\\ = 4.55\times10^-^3mol.$

$\sf Number\; of\; molecules\; of\; CO_2\; removed=10^2^1\\\\\ 1\; mol = 6.023\times10^2^3\;molecules\; of\; CO_2\\\\\ 10^2^1\;molecules=\dfrac{10^2^1}{6.023\times10^2^3}mol\\\\\ =1.66\times10^-^3mol$

$\sf CO_2\; left=(4.55-1.66)\times10^-^3mol\\\\\ = \sf {2.89\times 10^-^3 mol}$