Question

Using Dalton's law of partial pressures, you can find the pressure of the hydrogen to be 735.5 mmHg. Is this pressure to the correct number of significant digits according to the pressures used to calculate it?

Answer 1

Using Dalton's law, the partial pressure of hydrogen is correctly expressed as 735.5 mmHg if the pressures involved in the calculation are also provided to at least three significant digits.

Step-by-step explanation:

Dalton's law states that the total pressure in a mixture of non-reacting gases is the sum of the partial pressures of the individual gases. To determine if the pressure of the hydrogen gas is expressed with the correct number of significant digits, we must consider the significant digits in the pressures used for the calculation.

Given the example of a total pressure being the sum of 600 mm Hg and 1800 mm Hg to equal 2400 mm Hg, we see that each measurement is given to at least two significant digits. Therefore, reporting the partial pressure of hydrogen as 735.5 mmHg could be appropriate if the initial pressures that were added to find the total pressure were also measured to at least three significant digits.