Answer:
For 1: 6.68 g of nitrogen dioxide will contain [tex]8.73\times 10^{22}[/tex] number of molecules
For 2: The given amount of nitrogen dioxide molecules has a mass of 41.31 g.
Explanation:
According to the mole concept:
1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of molecules
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)
We are given:
Mass of nitrogen dioxide = 6.68 g
Molar mass of nitrogen dioxide = 46 g/mol
Putting values in equation 1, we get:
[tex]\text{Moles of nitrogen dioxide}=\frac{6.68g}{46g/mol}=0.145mol[/tex]
Using above concept:
If 1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of molecules
So, 0.145 moles of nitrogen dioxide will contain = [tex](0.145\times 6.022\times 10^{23})=8.73\times 10^{22}[/tex] number of molecules
Hence, 6.68 g of nitrogen dioxide will contain [tex]8.73\times 10^{22}[/tex] number of molecules
We are given:
Molecules of nitrogen dioxide = [tex]5.41\times 10^{22}[/tex] molecules
Using the above concept:
If [tex]6.022\times 10^{23}[/tex] number of molecules are present in 1 mole of a compound
So, [tex]5.41\times 10^{22}[/tex] number of molecules will be present in = [tex]\frac{1mol}{6.022\times 10^{23}}\times 5.41\times 10^{22}=0.898[/tex] moles of nitrogen dioxide
We know, molar mass of nitrogen dioxide = 46 g/mol
Using equation 1:
[tex]0.898mol=\frac{\text{Mass of nitrogen dioxide}}{46g/mol}\\\\\text{Mass of nitrogen dioxide}=0.898mol\times 46g/mol=41.31g[/tex]
Hence, the given amount of nitrogen dioxide molecules has a mass of 41.31 g.