Answer to Question #208542 in General Chemistry for neil

Question

The concentration of CO2 in air can be determined by an indirect acid–base titration. A sample of the air is bubbled through a solution containing an excess of Ba(OH)2, precipitating BaCO3. The excess Ba(OH)2 is back titrated with HCl. In a typical analysis, a 3.5-L sample of air was bubbled through 50.00 mL of 0.0200 M Ba(OH)2. Back titrating with 0.0316 M HCl requires 38.58 mL to reach the end point. Determine the parts per million of CO2 in the sample of air, given that the density of CO2 at the temperature of the sample is 1.98 g/L.

Answer 1

$ppM = \frac{1.98}{38.58}×50=2.566$