Question

Magnesium metal is reacted with hydrochloric acid to produce hydrogen gas. A sample of hydrogen gas is collected over water in a eudiometer at 28.0°C. The atmospheric pressure is 786 mmHg. Determine the pressure (in atm) of the hydrogen gas produced.

Answer 1

The pressure of hydrogen gas produced is 0.997 atm

Using the standard table of temperature and water vapour pressure;

• At 28.0°C, the water vapour pressure = 28.3 mmHg
• The pressure of hydrogen gas (H₂) collected over water is:

• = $\mathbf{P_{moist\ gas } = 786 mmHg}$

Recall that:

$\mathbf{P_{moist \ gas} = P_{dry \ gas} + P_{water vapor}}$

where;

• the dry gas = hydrogen gas

$\mathbf{ P_{dry \ gas} = P_{moist \ gas} - P_{water vapor}}$

$\mathbf{ P_{dry \ gas} = (786- 28.3) mmHg}}$

$\mathbf{ P_{dry \ gas} = (757.7) mmHg}}$

We know that 1 atmospheric pressure = 760 mmHg

∴

757.7 mmHg will be:

$\mathbf{=\dfrac{757.7 \ mmHg \times 1 \ atm}{760 \ mmHg}}$

= 0.997 atm

Therefore, we can conclude that the pressure of hydrogen gas produced is 0.997 atm

Learn more about partial pressure here;

https://brainly.com/question/14281129?referrer=searchResults