Gas Stoichiometry Worksheet Laws we have learned to solve each of the following problems: Each of the chemical equations must first be balanced. Show all your work for credit: written calculation, carbon dioxide gas is released according to the following equation: CaCO3 (s) -> CaO (s) + CO2 (g) What volume of CO2 (g), measured at STP, is produced when 15.2 grams of CaCO3 (s) is heated?
The Correct Answer and Explanation is:
To solve this gas stoichiometry problem, we’ll follow a structured approach. The given reaction is:
CaCO₃ (s) → CaO (s) + CO₂ (g)
Step 1: Balance the Chemical Equation
This equation is already balanced. One mole of calcium carbonate decomposes to form one mole of calcium oxide and one mole of carbon dioxide gas.
Step 2: Calculate the Molar Mass of CaCO₃
- Ca = 40.08 g/mol
- C = 12.01 g/mol
- O₃ = 3 × 16.00 = 48.00 g/mol
- Total = 40.08 + 12.01 + 48.00 = 100.09 g/mol
Step 3: Convert Mass of CaCO₃ to Moles
Given: 15.2 grams of CaCO₃Moles of CaCO₃=15.2 g100.09 g/mol≈0.152 mol\text{Moles of CaCO₃} = \frac{15.2 \text{ g}}{100.09 \text{ g/mol}} ≈ 0.152 \text{ mol}Moles of CaCO₃=100.09 g/mol15.2 g≈0.152 mol
Step 4: Use Mole Ratio to Find Moles of CO₂
From the balanced equation, 1 mole of CaCO₃ produces 1 mole of CO₂, so:Moles of CO₂=0.152 mol\text{Moles of CO₂} = 0.152 \text{ mol}Moles of CO₂=0.152 mol
Step 5: Use STP Conditions to Find Volume of CO₂
At STP (Standard Temperature and Pressure), 1 mole of any gas occupies 22.4 liters.Volume of CO₂=0.152 mol×22.4 L/mol=3.4048 L\text{Volume of CO₂} = 0.152 \text{ mol} × 22.4 \text{ L/mol} = 3.4048 \text{ L}Volume of CO₂=0.152 mol×22.4 L/mol=3.4048 L
Rounded to 3 significant figures:3.40 liters of CO₂\boxed{3.40 \text{ liters of CO₂}}3.40 liters of CO₂
Explanation:
Gas stoichiometry involves calculations that relate quantities of reactants and products in a chemical reaction involving gases. In this problem, calcium carbonate (CaCO₃) decomposes when heated, producing calcium oxide (CaO) and carbon dioxide gas (CO₂). We are given a mass of CaCO₃ and asked to find the volume of CO₂ produced at standard temperature and pressure (STP), which is defined as 0°C and 1 atm pressure. Under these conditions, one mole of any ideal gas occupies 22.4 liters.
The first step is confirming that the equation is balanced, which it is—each side of the equation contains one calcium, one carbon, and three oxygen atoms. Next, we calculate the molar mass of CaCO₃ by summing the atomic masses of calcium, carbon, and oxygen atoms. Using this molar mass, we convert the given mass of CaCO₃ into moles.
Once we have the number of moles of CaCO₃, we use the mole ratio from the balanced equation to determine the number of moles of CO₂ that will be produced. Here, the mole ratio is one to one, meaning the number of moles of CO₂ equals the number of moles of CaCO₃. Finally, we multiply the number of moles of CO₂ by the molar volume of a gas at STP to find the volume in liters.
The final answer is 3.40 liters of CO₂ gas.
