Question

How many grams of CaCl₂ (molar mass= 111 g/mol) are needed to prepare 100. mL of 0.100 M Cl(aq) ions?

A
B
C
O
0.555 g
1.11 g
2.22 g
5.55 g
↓

Answer 1

Answer: 0.555 g

Step-by-step explanation:

We need a total of
`(0.1)(0.100)=0.01` moles of chlorine ions.

For every 1 mole of calcium chloride, there are 2 moles of chlorine ions. So, we need
`0.005` moles of calcium chloride.

The mass of 0.005 moles of calcium chloride is
`(0.005)(111)=0.555` grams.