Question

Calculate the number o fatoms of each kind in 5.3 grams of sodium carbonate.

Answer 1

Moles of ==0.05
so moles of Na=0.05×2=0.1
moles of C=0.05×1=0.05
moles of O=0.05×3=0.15
we can now find the no. of atoms of each type by multiplying the no. of moles by Avagadro's constant.
number of molecules of Na = 0.1 $\times 6.02\times {10}^{2}3$ = $6.02\times {10}^{22}$
number of molecules of C = 0.05 $\times 6.02\times {10}^{2}3$ = $0.301\times {10}^{23}$
number of molecules of O = 0.15 $\times 6.02\times {10}^{2}3$ = $0.903\times {10}^{23}$