ST OIC H IOM Etr Ic determination of magnesium by gas displacement

Answer 1

Gas displacement is a method used in the determination of magnesium content in a sample. The principle behind this technique is that magnesium reacts with hydrochloric acid to produce hydrogen gas according to the following reaction:

Mg + 2HCl → MgCl2 + H2

The amount of hydrogen gas produced is directly proportional to the amount of magnesium present in the sample. By measuring the volume of hydrogen gas displaced in a closed system, the magnesium content can be calculated.

To perform the gas displacement determination of magnesium, the sample is first dissolved in hydrochloric acid. The hydrogen gas generated from the reaction is collected in a graduated cylinder filled with water or through a gas burette. The volume of gas displaced is then measured, and the magnesium content is calculated using the ideal gas law equation:

PV = nRT

where P is the pressure, V is the volume of the gas, n is the number of moles of gas, R is the gas constant, and T is the temperature.

By knowing the volume of gas displaced, the pressure, temperature, and the molar volume of hydrogen gas at a given temperature and pressure, the amount of magnesium present in the sample can be accurately determined.

Overall, the gas displacement method is a reliable and accurate technique for the determination of magnesium content in a sample. It is commonly used in various industries such as pharmaceuticals, food, and environmental analysis.