If 6.00 g of carbon is burned completely, what volume of carbon dioxide gas is released at STP?
A. 6.0 L
B. 11.2 L
C. 22.4 L
D. 134.4 L
Answer (2)
When 6.00 g of carbon is burned completely, it produces approximately 11.2 L of carbon dioxide gas at STP. This is calculated using the number of moles of carbon and the fact that at STP, 1 mole of gas occupies 22.4 L. Thus, the correct answer is option B.
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Calculate the number of moles of carbon: n C = 12.01 g/mol 6.00 g = 0.4995836802664446 mol .
Determine the number of moles of carbon dioxide produced: n C O 2 = n C = 0.4995836802664446 mol .
Calculate the volume of carbon dioxide at STP: V C O 2 = 0.4995836802664446 mol × 22.4 mol L = 11.190674437968358 L .
The volume of carbon dioxide released is approximately 11.2 L .
Explanation
Problem Analysis and Strategy We are given that 6.00 g of carbon is burned completely, and we need to find the volume of carbon dioxide gas released at Standard Temperature and Pressure (STP). At STP, 1 mole of any gas occupies 22.4 L. First, we need to determine the number of moles of carbon that were burned.
Calculating Moles of Carbon To find the number of moles of carbon, we use the formula: n = M m where:
n is the number of moles
m is the mass of the substance (in grams)
M is the molar mass of the substance (in g/mol)
The molar mass of carbon (C) is approximately 12.01 g/mol. So, for 6.00 g of carbon: n C = 12.01 g/mol 6.00 g = 0.4995836802664446 mol Rounding to a reasonable number of significant figures, we get approximately 0.500 mol of carbon.
Determining Moles of Carbon Dioxide The balanced chemical equation for the combustion of carbon to form carbon dioxide is: C + O 2 → C O 2 From the balanced equation, 1 mole of carbon (C) produces 1 mole of carbon dioxide ( C O 2 ). Therefore, the number of moles of C O 2 produced is equal to the number of moles of carbon burned: n C O 2 = n C = 0.4995836802664446 mol So, we have approximately 0.500 mol of C O 2 .
Calculating Volume of Carbon Dioxide at STP At STP, 1 mole of any gas occupies a volume of 22.4 L. Therefore, to find the volume of C O 2 produced, we multiply the number of moles of C O 2 by the molar volume at STP: V C O 2 = n C O 2 × 22.4 mol L V C O 2 = 0.4995836802664446 mol × 22.4 mol L = 11.190674437968358 L Rounding to three significant figures, the volume of C O 2 released is approximately 11.2 L.
Final Answer Therefore, if 6.00 g of carbon is burned completely, the volume of carbon dioxide gas released at STP is approximately 11.2 L.
Examples
Understanding the volume of gases produced in chemical reactions is crucial in many real-world applications. For example, in environmental science, knowing the amount of carbon dioxide released from burning fossil fuels helps scientists estimate the impact on climate change. In industrial chemistry, calculating the volume of gas produced in a reaction is essential for designing reactors and ensuring safety. In everyday life, this concept is used to understand how much carbon dioxide is produced by cars and other combustion engines, contributing to informed decisions about transportation and energy consumption.
