144. Solving a chemistry problem

144. Solving a chemistry problem

78.For the determination of calcium in the air of a cement plant, an air sample of 100 was taken. Air passed through an acid trap. As a result, the analyzed solution with a volume of 500.00 ml was obtained. For the determination of calcium used the method of comparison. A standard solution of calcium with a concentration of 0.050 μg / ml had a radiation intensity of 16 units. The radiation intensity of the analyzed solution was found to be 35 units. Determine the calcium concentration in the air (mg / l).