Question

What mass of water must be added to 50g of NaCl to make 50% mass percentage of the solution

Answer 1

percentage concentration is as follows:
mass of solute       x 100%mass of solution
mass of solute = 5g of NaClmass of solution = mass of NaCl + mass of water(let it be x)= 5g+xg% concentration= 5%
Therefore,  5%  = 5g        by 100%                            (5+x)g                                5= 500       cross multiply                     5+x            500= 25 + 5x           500-25=5x           5x=475 ......divide both sides by 5 to find x              x = 95g
Therefore the mass of water to be added =  95 grams