Answer:
9.35g
Explanation:
The molarity equation establishes that:
[tex]\textrm{molarity}=\frac{\textrm{moles of solute}}{\textrm{liters of solution}}[/tex]
So, we have information about molarity (2M) and volume (80 ml=0.08 l), with that, we can find the moles of solute:
[tex]\textrm{moles of solute}=\textrm{molarity}*\textrm{liters of solution}[/tex]
[tex]\textrm{moles of solute}= 0.08 \textrm{ l} *2\textrm{ M} = 0.16 \textrm{ mol}[/tex]
The mathematical equation that establishes the relationship between molar weight, mass and moles is:
[tex]\textrm{molar weight}= \frac{\textrm{mass}}{\textrm{moles}}[/tex]
[tex]\textrm{MW}= \frac{\textrm{m}}{\textrm{n}}[/tex]
We have MW (58.44g/mole) and n (0.16 mol), and we need to find m (grams of salt needed) to solve the problem:
[tex]\textrm{m} = \textrm{MW * n}= 58.44\frac{\textrm{g}}{\textrm{mol}} * 0.16 \textrm{ mol} = 9.35 \textrm{ g}[/tex]
