If you started with 0.151 mol of N2 and 0.453 mol of H2, and they completely reacted in the reaction vessel, determine the total moles of gas particles (n) there are during the initial and final conditions. Additionally, determine the ratio of the number of gas particles in the products to that of the reactants, then complete the statements below.
• Initially, there are _____ of gas particles (ninit).
• After the reaction is completed, there are _____ of gas particles (nfin).
• Therefore, the ratio of product to reactant particles (nfin/ninit) is _____.
Balanced chemical equations include coefficients that describe the ratio between molecules or moles of reactants and products. This relationship would allow you to utilize pressure measurements to monitor the progress of a reaction between gases if the number of gas molecules on each side of the reaction is different. An example of a reaction that cannot be monitored in real time is the combustion of methane:
CH4(g) + 2 O2(g) → CO2(g) + 2 H2O(g) + heat
The temperature at which the reaction takes place would result in the formation of water in the gas phase, which means that three moles of reactants (one mole of methane and two moles of oxygen) would form three moles of product (one mole of carbon dioxide and two moles of water vapor). However, the percent yield of a reaction could eventually be determined once the product mixture is permitted to cool, and the pressure will reflect the change in the number of moles of gas since water vapor will condense into the liquid phase and carbon dioxide would be the only product gas. We will explore several gas reactions in which the number of gaseous molecules differs between the reactants and products.
Click on the image below to explore this simulation, which allows you run reactions between various gases and specify their amounts. When you click the simulation link, you will be able to select among Overview, Learning Outcomes, and Experiment tabs.
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the Stoichiometry concept. You can view video lessons to learn Stoichiometry. Or if you need more Stoichiometry practice, you can also practice Stoichiometry practice problems.