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CHEMISTRY, M2 EQ-Bank 7 MC

According to Gay-Lussac's Law, the pressure of a gas is directly proportional to which quantity, assuming the volume and the number of moles are constant?

  1. Volume
  2. Temperature
  3. Moles
  4. Pressure
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\(B\)

Show Worked Solution
  • Gay-Lussac’s Law states that the pressure of a gas is directly proportional to its temperature, provided the volume and number of moles remain constant. 
  • This can be written mathematically like  \(\dfrac{P_1}{T_1}=\dfrac{P_2}{T_2}\).

\(\Rightarrow B\)

CHEMISTRY, M2 EQ-Bank 6 MC

A sealed container of gas is heated, causing the temperature of the gas to increase from 300 K to 450 K, while the volume of the gas remains constant. If the initial pressure of the gas was 120 kPa, what will the new pressure be?

  1. 180 kPa
  2. 150 kPa
  3. 90 kPa
  4. 80 kPa
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\(A\)

Show Worked Solution
  • Using Gay-Lussac’s Law:  \(\dfrac{P_1}{T_1}=\dfrac{P_2}{T_2}\)
  •    \(P_2=\dfrac{P_1T_2}{T_1}=\dfrac{120 \times 450}{300}=180\ \text{kPa}\)

\(\Rightarrow A\)