A chemist prepares a solution of vanadium(III) bromide (VBr) by measuring out 0.12 g of VBr into a 300 ml. volumetric flask and filling to the mark with distilled water. Calculate the molarity of Branions in the chemist's solution. Be sure your answer is rounded to significant digits.

Respuesta :

Answer: The molarity of bromine ions in the chemist's solution is [tex]4.06\times 10^{-3}M[/tex]

Explanation:

To calculate the molarity of solution, we use the equation:

[tex]\text{Molarity of the solution}=\frac{\text{Mass of solute}}{\text{Molar mass of solute}\times \text{Volume of solution (in L)}}[/tex]

Given mass of vanadium(III) bromide = 0.12 g

Molar mass of vanadium(III) bromide = 295.65 g/mol

Volume of solution = 300 mL

Putting values in above equation, we get:

[tex]\text{Molarity of solution}=\frac{0.12\times 1000}{295.65g/mol\times 300}\\\\\text{Molarity of solution}=1.353\times 10^{-3}M[/tex]

The chemical formula of vanadium(III) bromide is [tex]VBr_3[/tex]

1 mole of vanadium(III) bromide produces 1 mole of [tex]V^{3+}[/tex] ions and 3 moles of [tex]Br^-[/tex] ions

Molarity of bromine ions = [tex](3\times 1.353\times 10^{-3})=4.06\times 10^{-3}M[/tex]

Hence, the molarity of bromine ions in the chemist's solution is [tex]4.06\times 10^{-3}M[/tex]