# Question #c27d4

Feb 11, 2018

Molarity$=$ (Number of moles of Solute)/(Volume of Solution in Litre)

#### Explanation:

Here Solute is $N a C l$(s) and solution is the $N a C l$(aq)

So, here we have to make $1 L i t r e$ of $4 M$ $N a C l$ solution.

$\Rightarrow$ Molarity of $N a C l$ solution $=$ $4 M$

and,

Volume of the $N a C l$ solution $=$ $1 L$

The Molar mass of $N a C l$ = $58.44$ g/mol

Using the formula of Molarity here we get :-

Molarity of $N a C l$ solution $=$ (Number of moles of $N a C l$)
/ (Volume of the $N a C l$ solution in Litre)

$\Rightarrow$ $4 M$ $=$ (Number of moles of $N a C l$)/$1 L$

$\Rightarrow$ $4 M$x$1 L$ $=$ Number of moles of $N a C l$

$\therefore$ Number of moles of $N a C l$ $=$ $4$ moles

Amount of $N a C l$ needed $=$ $4$ moles x $58.44$g/mol

$\Rightarrow$Amount of $N a C l$ needed$= 233.76$g$= 0.233$kg