Consider the following reaction:
2 CH3OH + 3O2 to form 2 CO2 + 4 H20
Each of the following molecular diagrams represents an initial mixture of the reactants. How many CO2 molecules would be formed by complete reaction in each case?
How do I use the molecular diagrams to help me answer the question?
I suspect you are to find the limiting reactant, either O2 or CH3OH. You need a ratio of 2:3 to react completly
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For the first diagram, there are 4 CH3OH molecules and 6 O2 molecules. This means that the limiting reactant is CH3OH, and the reaction will produce 2 CO2 molecules.
For the second diagram, there are 6 CH3OH molecules and 6 O2 molecules. This means that the limiting reactant is O2, and the reaction will produce 2 CO2 molecules.
For the third diagram, there are 8 CH3OH molecules and 6 O2 molecules. This means that the limiting reactant is O2, and the reaction will produce 2 CO2 molecules.
To use the molecular diagrams to answer the question and determine how many CO2 molecules would be formed in each case, you need to identify the limiting reactant. The limiting reactant is the substance that will be completely consumed in the reaction, thus limiting the amount of product that can be formed.
In this case, you are given two possible initial mixtures of reactants in molecular diagrams. To identify the limiting reactant, you need to compare the number of moles or molecules of each reactant present.
The balanced equation tells us that the ratio of CH3OH to O2 is 2:3. So, for every 2 moles of CH3OH, you need 3 moles of O2 to react completely.
In each of the molecular diagrams, count the number of CH3OH and O2 molecules. Determine how many moles of each reactant are present by using Avogadro's number (6.022 x 10^23 molecules per mole).
Compare the mole ratios of CH3OH to O2 in each case. The reactant with the lower mole ratio (closest to the 2:3 ratio) will be the limiting reactant.
Once you have identified the limiting reactant, you can use stoichiometry to calculate the number of moles of CO2 that will be formed. From the balanced equation, you know that 2 moles of CH3OH will produce 2 moles of CO2.
Multiply the number of moles of the limiting reactant by the stoichiometric ratio of CO2 to the limiting reactant to determine the number of moles of CO2 formed.
Finally, convert the moles of CO2 to the number of CO2 molecules by multiplying by Avogadro's number.
Repeat this process for each molecular diagram to determine the number of CO2 molecules formed in each case.
To use the molecular diagrams to answer the question, you can analyze the number of molecules of each reactant present in each diagram and determine which reactant will be the limiting reactant. The limiting reactant is the one that will be completely consumed, limiting the amount of product that can be formed.
In this reaction, the stoichiometric ratio between CH3OH and O2 is 2:3. This means that for every 2 molecules of CH3OH, you need 3 molecules of O2 to react completely.
Now, let's analyze each molecular diagram:
1. If the diagram shows 4 CH3OH molecules and 6 O2 molecules, you can see that the ratio is already in the correct stoichiometric ratio. Therefore, both reactants would be completely consumed, resulting in the formation of 2 CO2 molecules.
2. If the diagram shows 3 CH3OH molecules and 5 O2 molecules, you can see that there is an excess of O2 compared to the stoichiometric ratio. In this case, the CH3OH will be the limiting reactant. Since the stoichiometry is 2:3, only 1.5 molecules of O2 would be required to react completely with the 3 CH3OH molecules. However, since we cannot have half a molecule, the limiting reactant, CH3OH, will completely react and only 1.5 molecules of O2 will be consumed. Therefore, only 1 CO2 molecule can be formed.
3. If the diagram shows 6 CH3OH molecules and 4 O2 molecules, you can see that there is an excess of CH3OH compared to the stoichiometric ratio. In this case, O2 will be the limiting reactant. Since the stoichiometry is 2:3, only 2/3 (approximately 0.67) of the CH3OH molecules would be required to react completely with the 4 O2 molecules. Therefore, only 2/3 of the CH3OH will be consumed, resulting in the formation of 1.33 (approximately 1) CO2 molecules.
So, to summarize:
- Diagram 1: 2 CO2 molecules formed
- Diagram 2: 1 CO2 molecule formed
- Diagram 3: 1 CO2 molecule formed (approximately)
I hope this helps! Let me know if you have any further questions.