Question

2.5 g of Glucose is dissolved in enough water to make 1 L of solution. What is the molarity (M) of the solution? How many moles of glucose are contained in 237 mL of the above glucose solution? What volume (L) of this glucose solution would contain .079 moles of glucose?

Answer 1

Answer:

• Molarity of the solution is - 0.138 M glucose or moles/litre.

• Number of moles of glucose contained in 237ml of glucose is - 0.0327 moles glucose.

• Volume of the glucose containing 0.79 moles of glucose is - 0.572 L of glucose .

Explanation:

• To find the molarity of the solution -:

we know , molar mass of glucose is 18.08 g

now , moles of glucose = $\frac{Mass}{molar mass}$

                                    =$\frac{2.5}{18.08}$

                               = 0.138 moles of glucose .

Molarity =$\frac{Mole}{ solution(in litre)}$

            = $\frac{0.138}{1}$

         =0.138 M glucose or moles/litre.

• To find number of moles of glucose contained in 237 ml glucose solution-:

      Number of moles of glucose contained in 237ml of glucose =$0.237 L\times \frac{0.138moles glucose}{Lof solution}$

= 0.0327 moles glucose.

• To find the volume of the glucose containing 0.79 moles of glucose -:

               = $.079 moles\times \frac{L (of solution)}{0.138moles glucose}$ (by using the molarity formula)

               = 0.572 L of glucose .

Hence ,

• Molarity of the solution is - 0.138 M glucose or moles/litre.

• Number of moles of glucose contained in 237ml of glucose is - 0.0327 moles glucose.

• Volume of the glucose containing 0.79 moles of glucose is - 0.572 L of glucose .