Question

Calculate the mass in grams of each of the followinga. 5.94 x 10^20 H2O2 moleculesb. 2.8 x 10^22 SO2 moleculesc. 4.5 x 10^25 O3 moleculesd. 9.85 x 10^19 CH4 molecules

Answer 1

Answer:

$0.0335\ \text{g}$

$2.978\ \text{g}$

$3586.84\ \text{g}$

$0.0026\ \text{g}$

Explanation:

Mass in grams is given by

$m=\dfrac{nM}{N_A}$

where

n = Number of molecules

$N_A$ = Avogadro's number = $6.022\times 10^{23}\ \text{mol}^{-1}$

M = Molar mass of molecule

Molar mass of $H_2O_2$ = 34.0147 g/mol

$n=5.94\times 10^{20}$

$m=\dfrac{5.94\times 10^{20}\times 34.0147}{6.022\times 10^{23}}\\\Rightarrow m=0.0335\ \text{g}$

Mass of $H_2O_2=0.0335\ \text{g}$

Molar mass of $SO_2$ = 64.066 g/mol

$n=2.8\times 10^{22}$

$m=\dfrac{2.8\times 10^{22}\times 64.066}{6.022\times 10^{23}}\\\Rightarrow m=2.978\ \text{g}$

Mass of $SO_2=2.978\ \text{g}$

Molar mass of $O_3$ = 48 g/mol

$n=4.5\times 10^{25}$

$m=\dfrac{4.5\times 10^{25}\times 48}{6.022\times 10^{23}}\\\Rightarrow m=3586.84\ \text{g}$

Mass of $O_3=3586.84\ \text{g}$

Molar mass of $CH_4$ = 16.04 g/mol

$n= 9.85\times 10^{19}$

$m=\dfrac{9.85\times 10^{19}\times 16.04}{6.022\times 10^{23}}\\\Rightarrow m=0.0026\ \text{g}$

Mass of $CH_4=0.0026\ \text{g}$