This document provides instructions for estimating the amount of barium (Ba) in a solution containing barium chloride, ferric chloride, and hydrochloric acid. Barium and ferric ions are separated by precipitating ferric hydroxide, then the filtrate is reacted with potassium dichromate to form a yellow barium chromate precipitate. The precipitate is weighed to calculate the amount of barium originally present in the solution. The procedure involves precipitation, filtration, acidification, a second precipitation, washing, drying, and weighing the barium chromate precipitate.