Question

A 0.674\,\text M0.674M0, point, 674, start text, M, end text cobalt(II) chloride (\text{CoCl}_2CoCl 2 ​ start text, C, o, C, l, end text, start subscript, 2, end subscript) solution is prepared with a total volume of 0.0750\,\text{L}0.0750L0, point, 0750, start text, L, end text. The molecular weight of \text{CoCl}_2CoCl 2 ​ start text, C, o, C, l, end text, start subscript, 2, end subscript is 128.9\,\dfrac{\text{g}}{\text{mol}}128.9 mol g ​ 128, point, 9, start fraction, start text, g, end text, divided by, start text, m, o, l, end text, end fraction.

Answer 1

The mass of this CoCl2 sample is 6.516 grams

Step-by-step explanation:

Step 1: Data given

Molarity of a cobalt(II) chloride (CoCl2) solution is 0.674 M

Volume of the solution is 0.0750 L

The molecular weight of CoCl2 is 128.9 g/mol

Step 2: Calculate moles CoCl2

Moles CoCl2 = molarity CoCl2 solution * volume solution

Moles CoCl2 = 0.674 M * 0.0750 L

Moles CoCl2 = 0.05055 moles

Step 3: Calculate mass of the CoCl2 sample

Mass CoCl2 = moles CoCl2 * molar mass CoCl2

Mass CoCl2 = 0.05055 moles * 128.9 g/mol

Mass CoCl2 = 6.516 grams

The mass of this CoCl2 sample is 6.516 grams