Question

18.066 X 1023 atoms of Na will represent how many grams of Na? Group of answer choices1 gram107.5 grams56 grams96 grams69 grams

Answer 1

1) Convert atoms to moles

Avogadro's number is 6.022*10^23

$molNa=18.066\cdot10^{23}atomsofNa\cdot\frac{1molNa^{}}{6.022\cdot10^{23}atoms_{}ofNa}^{}=3molNa_{}$

2) Convert moles to grams

The molar mass of Na is 22.990 g/mol

$gNa_{}=3molNa\cdot\frac{22.990_{}gNa}{1molNa_{}}_{}=68.97gNa_{}$

There are 18.066*10^23 atoms of Na in 69 grams of Na.