Chemistry · Stoichiometry
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By heating 25g of limestone (CaCO3) , the weight of carbon dioxide produced is:
- A
14 g
- B
71 g
- C
11 g
- D
2 g
- E
10 g
Limestone is primarily composed of calcium carbonate (CaCO3). When heated, it decomposes according to the reaction:
CaCO3 --> CaO + CO2
From the stoichiometric relationship, 100g of CaCO3 decomposes to produce 44g of CO2. Therefore, for 25g of CaCO3, the amount of CO2 produced is calculated as follows:
(25g CaCO3 / 100g CaCO3) * 44g CO2 = 11g CO2
Thus, the correct answer is 11g. Other options either overestimate or underestimate this calculated mass based on incorrect stoichiometric assumptions.
This option incorrectly assumes a different stoichiometric proportion.
This value is much higher than the possible mass of CO2 produced, considering the initial mass of limestone.
Based on stoichiometry: 100g CaCO3 produces 44g CO2, hence 25g CaCO3 produces 11g CO2. This is the correct answer.
This value underestimates the mass of CO2 produced from 25g of CaCO3.
This value is close but slightly underestimates the correct stoichiometric calculation.
Tagged under Chemistry · Stoichiometry · 2011