The mass percent for a solution : 35.42%
Further explanation
The concentration of a substance can be expressed in several quantities such as moles, percent (%) weight/volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.
![\tt \%mass=(mass~solute)/(mass~solution)* 100\%](https://img.qammunity.org/2021/formulas/chemistry/college/ynoy877u21koviq5d9qmkktww4x7b8s03i.png)
mass solute = 85 g
mass solution = 85 + 155 = 240 g
![\tt \%mass=(85)/(240)* 100\%=35.42\%](https://img.qammunity.org/2021/formulas/chemistry/college/fh230jfvbtgrse0uu35x92rwg56m3if7ul.png)