Volume Problems
Answer the following questions. Scan and upload your questions and answers to your student section labeled Volume Volume Problems.
Identify the following chemical equations by type.
1. If an electric discharge produces 500 cm3 of ozone (O3), how many cm3 of oxygen (O2) are required?
3O2(g) ---> 2O3(g)
2. When 2.75 dm3 of O2 react with an excess of glucose (C6H12O2), according to the reaction below, what volume of carbon dioxide will be produced?
6O2(g) + C6H12O6(s) ---> 6H2O(g) + 6CO2(g)
3. If an excess of nitrogen gas reacts with 25.0 L of hydrogen gas, according to the reaction below, how many L of ammonia will be produced?
N2(g) + 3H2(g) ---> 2NH3(g)
4. How many cm3 of oxygen would be required to react completely with 250.0 cm3 of hydrogen gas according to the reaction below?
2H2(g) + O2(g) ---> 2H2O(g)
Do you have any ideas?
For #1. you can treat volumes of gases as if they were mols; therefore,
volume O2 required = 500 x (3 mols O2/2 mols O2) = 500 x 3/2 = ?
To solve these volume problems, we need to use the stoichiometry of the chemical equations.
1. To find the volume of oxygen required to produce 500 cm3 of ozone, we need to use the stoichiometric ratio from the balanced equation: 3 moles of oxygen produce 2 moles of ozone.
First, convert the volume of ozone to moles using the ideal gas law:
PV = nRT
n = PV/RT
Substitute the values: P = 1 atm, V = 500 cm3, R = 0.0821 L·atm/mol·K, and T = given temperature (in Kelvin).
Now you have the number of moles of ozone produced.
Next, use the stoichiometric ratio from the balanced equation to find the moles of oxygen required.
Finally, convert the moles of oxygen to volume using the ideal gas law.
2. To find the volume of carbon dioxide produced when 2.75 dm3 of oxygen reacts with an excess of glucose, we will use the stoichiometric ratio from the balanced equation: 6 moles of oxygen produce 6 moles of carbon dioxide.
First, convert the volume of oxygen to moles using the ideal gas law (since we are given the volume in dm3).
Next, use the stoichiometric ratio to find the moles of carbon dioxide produced.
Finally, convert the moles of carbon dioxide to volume using the ideal gas law.
3. To find the volume of ammonia produced when an excess of nitrogen gas reacts with 25.0 L of hydrogen gas, we will use the stoichiometric ratio from the balanced equation: 1 mole of nitrogen gas reacts with 3 moles of hydrogen gas to produce 2 moles of ammonia.
First, convert the volume of hydrogen gas to moles using the ideal gas law.
Next, use the stoichiometric ratio to find the moles of ammonia produced.
Finally, convert the moles of ammonia to volume using the ideal gas law.
4. To find the volume of oxygen required to react completely with 250.0 cm3 of hydrogen gas, we will use the stoichiometric ratio from the balanced equation: 2 moles of hydrogen gas react with 1 mole of oxygen to produce 2 moles of water.
First, convert the volume of hydrogen gas to moles using the ideal gas law.
Next, use the stoichiometric ratio to find the moles of oxygen required.
Finally, convert the moles of oxygen to volume using the ideal gas law.