Question

The mass of a quantity of NiCl2

Answer 1

Answer: The correct answer is Option A.

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of nickel chloride = 24.6 g

Molar mass of nickel chloride = 129.6 g/mol

Putting values in above equation, we get:

$\text{Moles of }NiCl_2=\frac{24.6g}{129.6g/mol}=0.19mol$

Formula units is defined as lowest whole number ratio of ions in an ionic compound. It is calculate by multiplying the number of moles by Avogadro's number which is $6.022\times 10^{23}$

We are given:

Number of moles of nickel chloride = 0.19 moles

Number of formula units = $0.19\times 6.022\times 10^{23}=1.1\times 10^{23}$

Hence, the correct answer is Option A.

Answer 2

Not sure, is it :
B.
 1.9 3 1027 NiCl2
formula units