Question

Calculate the molarity of a solution containing 5 gram of nios in 450 ml solution

Answer 1

molarity= weight of solute in kilogram/volume of the solution in litres =0.005/0.45=5×10^-3/4.5×10^-1=1.11×10^-2=0.0111 molar.

Answer 2

Correct Question-

Calculate the molarity of a solution containing 5 gram of NaOH in 450 ml solution.

SolutiOn-

Moles of NaOH

$= \frac{5 \: g}{40 \: g \: mol {}^{ - 1} } = 0.125 \: mol$

Volume of solution in liters

= 450 mL /1000 mL L -¹

We know that ,

$\boxed{ \red{molarity \: = \frac{moles \: of \: solute}{volume \: of \: solution \: in \: litre} }}$

$= \frac{0.125 \: mol \times 1000 \: ml \: l {}^{ - 1} }{450 \: ml }$

= 0.278 M

= 0.278 mol L-¹

$\tt{ \red= 0.278 \: mol \: dm {}^{ - 3} }$