Question

If you wanted to make 0.800 Liters of a 0.531 M solution of Nickel(II) chloride, NiCl2, how many grams of NiCIZ

Answer 1

Answer:

• 54.8g

Explanation:

1. Calculate the number of moles of NiCl₂

a) Identify the known variables

• V =0.800 liters
• M = 0.531M
• n = ?

b) Formula

       $M=\dfrac{n}{V}$

c) Clear n

        $n=M\times V$

g) Substitute and compute

         $n=0.531M/times 0.800liters=0.4248mol$

2. Convert moles to grams

a) molar mass of NiCl₂

• 129g/mol (shown in the problem)

b) Unit canceling method

Use the factors in order to cancel the units to obtain grams

      $0.4248mol\times 129\dfrac{g}{mol}=54.7992g$

Note that the mol unit appears on the numerator and denominator, so it cancels leaving just g (grams).

c) Round to 3 signficant figures

     $54.8g$