Question

Explain how you would prepare a solution of sucrose with a molarity of 0.25.

Answer 1

Solution of 0.25 M is prepared in two steps,

1) Calculate Amount of Solute:

                                Molar Mass of Solute:  342.3 g/mol

As we know,
                            Molarity  =  Moles / 1 dm³
or,
                            Moles     =  Molarity × 1 dm³
Putting Values,
                            Moles     =  0.25 mol.dm⁻³ × 1 dm³

                            Moles     =  0.25 moles

Now, find out mass of sucrose,
As,               
                            Moles      =   Mass / M.mass
or,
                            Mass       =  Moles × M.mass
Putting Values,
                            Mass       =  0.25 mol × 342.3 g.mol⁻¹

                            Mass       =  85.57 g

2) Prepare Solution:
                               Take Volumetric flask and add 85.57 g of sucrose in it. Then add distilled water up to the mark of 1 dm³. Shake well! The solution prepared is 0.25 M in 1 Liter.