Answer:
[tex]0.85 mol Zn(NO_3)_2[/tex]
Explanation:
we calculate the molecular mass of the compound
[tex]Zn= 65 g/mol\\N= 14 g/mol\\O= 16 g/mol[/tex]
[tex]Zn(NO_3)_2= 65+2(14)+ 6(16)=189 g/mol[/tex]
We know that in a 1 mol of [tex]Zn(NO_3)_2[/tex] there are 189 grams
To calculate how many moles of [tex]Zn(NO_3)_2[/tex] are in 161.50 grams we apply a simple rule of three
[tex]189g \longrightarrow 1mol\\161.5g \longrightarrow x \\ x=\frac{(161.5)(1)}{189}\\ x= 0.85 mol[/tex]
[tex]0.85 mol Zn(NO_3)_2[/tex]