Question

500 ml of glucose solutions contain 90gm of glucose. The concentration of the solution is?​

Answer 1

since the sol. contains 6.02 x 10^22 molecules,  

the no. of moles of glucose = 6.02 x10^22 / N(avogadro)  

                                        = 6.02 x 10^22 /6.022 x 10^23

                                        = 0.1 moles (approx.)

volume of solution = 500 ml. = 0.5 L

therefore, concentration of solution in terms of molarity (since they haven’t specified a method, molarity is the quickest form to express in, in this case)  

molarity = no. of moles of solute / volume of solution( in litres)

            = 0.1 / 0.5  

           = 0.2 M

Answer 2

Given:

The volume of glucose solution= 500 ml

Amount of solute glucose in the solution= 90 g

To find:

The concentration of the glucose solution=?

Solution:

• The concentration of the solution can be found in grams/mol or can be expressed in percentage composition in terms of %w/v.
• The concentration of the solution is based on the amount of the solute that is dissolved to form a solution (glucose in this case).
• To find the concentartion in %w/v steps are-

=> Concentration of glucose solution = $\frac{amount of glucose solute (in grams)}{volume of solution (in milliltres)}$ × 100

=> Concentration of glucose solution = $\frac{90 grams}{500 millilitres}$ × 100

=> Concentration of glucose solution = $\frac{90}{5}$

=> Concentration of glucose solution = 18 %g/ml

Hence, the concentration of glucose solution in %w/v is 18%.