Answer :
Final answer:
To calculate the total pressure in the hydrogen test tube during the electrolysis of water, the vapor pressure of water at 23°C should be added to the partial pressure of hydrogen (98.5 kPa). This sum will provide the total pressure in the test tube.
Explanation:
The student's question deals with the process of electrolysis of water, where electrical energy is used to decompose water into hydrogen and oxygen gas. To find the total pressure in the hydrogen test tube, it is important to consider the vapor pressure of water plus the partial pressure of the hydrogen gas collected. The vapor pressure of water is determined by the temperature of the water and varies accordingly.
At 23°C, the vapor pressure of water can be found in standard tables, and it is essential to add this pressure to the given partial pressure of hydrogen (98.5 kPa) to obtain the total pressure inside the test tube. Dalton's Law states that the total pressure is the sum of the partial pressures of all gases in a mixture. Thus, the student would need to use the correct vapor pressure value at 23°C, add this to the 98.5 kPa of hydrogen, to find the total pressure in the test tube.
Final answer:
The total pressure in the "hydrogen" test tube is 101.5 kPa, which includes the partial pressure of hydrogen and atmospheric pressure.
Explanation:
When determining the total pressure in a gas mixture, Dalton's law of partial pressures comes into play. According to this law, the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the individual gases. In this scenario, the partial pressure of hydrogen is given as 98.5 kPa.
As there is no other gas mentioned, the total pressure is simply the partial pressure of hydrogen plus any additional pressure due to other gases or factors. Thus, the total pressure in the "hydrogen" test tube can be calculated as 98.5 kPa (partial pressure of hydrogen) plus the atmospheric pressure, which at standard conditions is approximately 101.5 kPa. Hence, the total pressure in the test tube is 101.5 kPa.
Option: The correct option is C.
