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CHEMISTRY, M2 EQ-Bank 9

Aluminium carbonate reacts with nitric acid to produce aluminium nitrate, carbon dioxide, and water.

What volume of carbon dioxide will be produced if 15.0 g of aluminium carbonate is reacted and the gas is collected at 25°C and 100 kPa?   (5 marks)

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\(4.76\ \text{L}\) 

Show Worked Solution
  • The chemical equation for the reaction:
  •    \(\ce{Al2(CO3)3 + 6HNO3 -> 2Al(NO3)3 + 3CO2 + 3H2O}\)
  • \(\ce{n(Al2(CO3)3)}=\dfrac{m}{MM}=\dfrac{15.0}{2(26.98+3(12.01)+9(16)}=0.0641\ \text{mol}\)
  • The ratio of \(\ce{Al2(CO3)3:CO2 = 1:3}\)
  • \(\ce{n(CO2)}= 3 \times 0.0641 = 0.192\ \text{mol}\)
  • Using Avogadro’s Law:
  •    \(V=n \times V_{\text{molar}} = 0.192 \times 24.79 = 4.76\ \text{L}\) 

CHEMISTRY, M2 EQ-Bank 1-2 MC

Use the equation below to answer the following two questions: 

\(\ce{2C2H6(g) + 7O2(g) -> 4CO2(g) + 6H2O(l)}\)
 

Part 1

What volume of carbon dioxide would be produced by the combustion of 3.0 L of ethane gas \(\ce{C2H6(g)}\) in excess oxygen? (Assume the temperature and pressure remain the same)

  1. 6.0 L
  2. 3.0 L
  3. 1.5 L
  4. 0.5 L


Part 2

Whose law is applied when determining the volume relationships in the reaction above?

  1. Boyle's Law
  2. Gay-Lussac's Law
  3. Avogadro's Law
  4. Charles' Law
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Part 1: \(A\)

Part 2: \(C\)

Show Worked Solution

Part 1

  • From the chemical equation, the mole ratio of ethane to carbon dioxide is \(1:2\).
  • According to Avogadro’s Law, at the same temperature and pressure, the volume of gases is directly proportional to the number of moles.
  • Thus, from the equation, 1 volume of ethane produces 2 volumes of carbon dioxide.
  • The volume of carbon dioxide produced \(=2 \times 3.0 = 6.0\ \text{L}\)

\(\Rightarrow A\)

 

Part 2

  • When determining the volume relationships between gases in a chemical reaction, Avogadro’s Law is used.
  • Avogadro’s Law states that equal volumes of gases, at the same temperature and pressure, contain the same number of moles of gas.
  • The volumes of gas react in simple whole-number ratios, as shown in the balanced equation.

\(\Rightarrow C\)