160 ml of water was added to 140 g of a 15% sugar solution. What is the percentage of sugar

160 ml of water was added to 140 g of a 15% sugar solution. What is the percentage of sugar in the newly obtained solution?

Given:

m (solution) = 140 g;

w% (C6H12O6) = 15%;

V (H2O) = 160 ml;

To find:

w% (C6H12O6 in the final solution) -?

Decision:

1) Find the mass of sugar in the primary solution:

m (C6H12O6) = 140 g * 0.15 = 21 g;

2) Find the mass of added water:

m (H2O) = p * V = 1 g / ml * 160 ml = 160 g;

3) Find the mass of the solution after adding water:

m (solution) = 140 g + 160 g = 300 g;

4) Find the mass fraction of sugar in the resulting solution:

w% (C6H12O6) = m (C6H12O6): m (solution) * 100% = 21 g: 300 g * 100% = 7%.

Answer: w% (C6H12O6) = 7%.