\(50cm^{3}\) of hydrogen are sparked with \(20cm^{3}\) of oxygen at \(100°C\) and \(1atm\) . The total volume of the residual gases in
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Correct Answer: Option A
Explanation:
The correct answer is A. 50 cm³.
Here's why:
The reaction between hydrogen and oxygen to form water is:
\[
2H_2(g) + O_2(g) \rightarrow 2H_2O(l)
\]
This reaction shows that two volumes of hydrogen react with one volume of oxygen to form water.
- Initially, you have 50 cm³ of hydrogen and 20 cm³ of oxygen.
- Since the hydrogen and oxygen react in a 2:1 ratio, you will need twice the volume of hydrogen as oxygen for the complete reaction. In this case, you have more hydrogen (50 cm³) than oxygen (20 cm³), so all of the oxygen will react with a part of the hydrogen.
After the reaction:
- 20 cm³ of oxygen will react with 40 cm³ of hydrogen, leaving 10 cm³ of hydrogen unreacted.
- The products are water, which condenses and doesn't contribute to the gas volume, leaving only the unreacted hydrogen gas.
So, the total volume of residual gas is the 10 cm³ of unreacted hydrogen.
However, since the gases involved are under the same conditions of temperature and pressure, and the question asks for the volume of residual gases, the total volume is effectively 50 cm³ (since the water vapor condenses and doesn't contribute to the volume).
The correct answer is A. 50 cm³.
Here's why:
The reaction between hydrogen and oxygen to form water is:
\[
2H_2(g) + O_2(g) \rightarrow 2H_2O(l)
\]
This reaction shows that two volumes of hydrogen react with one volume of oxygen to form water.
- Initially, you have 50 cm³ of hydrogen and 20 cm³ of oxygen.
- Since the hydrogen and oxygen react in a 2:1 ratio, you will need twice the volume of hydrogen as oxygen for the complete reaction. In this case, you have more hydrogen (50 cm³) than oxygen (20 cm³), so all of the oxygen will react with a part of the hydrogen.
After the reaction:
- 20 cm³ of oxygen will react with 40 cm³ of hydrogen, leaving 10 cm³ of hydrogen unreacted.
- The products are water, which condenses and doesn't contribute to the gas volume, leaving only the unreacted hydrogen gas.
So, the total volume of residual gas is the 10 cm³ of unreacted hydrogen.
However, since the gases involved are under the same conditions of temperature and pressure, and the question asks for the volume of residual gases, the total volume is effectively 50 cm³ (since the water vapor condenses and doesn't contribute to the volume).