What is the percent by mass of NaHCO3 in a solution containing 20 g NaHCO3 dissolved in 600 g water?

The solute of the solution is the substance that is dissolved (`~NaHCO_3` )

The solvent of the solution is the substance that the solute was dissolved in (`~H_2O` )

The solution is the solute and the solvent together.

To calculate the percent of something, you divide the "part" (the solute) by the "whole" (solution).

From the question, we know the following:

• The mass of the solute = 20 g `~NaHCO_3`

• The mass of the solvent = 600 g `~H_2O`

In order to get the mass of the solution, we must add the mass of the solute to the mass of the solvent:

   mass of solution = mass of solute + mass of solvent

                           = 20 g + 600 g 

                           = 620 g `~NaHCO_3` solution

The formula used to calculate percent by mass is:

   % by mass = [mass of solute/mass of solution] x 100

                    = [20 g/620 g] x 100  

                    = 3.2 %