WorksheetsBalancing Equations and Air Composition
Total questions: 15
Worksheet time: 8mins
What is the balanced equation for the combustion of methane (CH4)?
CH4 + 3 O2 -> 2 CO2 + 2 H2O
CH4 + O2 -> C + 2 H2O
CH4 + 2 O2 -> CO2 + 2 H2O
CH4 + O2 -> CO + H2O
How many molecules of oxygen are needed to completely burn one molecule of propane (C3H8)?
3
4
6
5
What is the primary gas found in the Earth's atmosphere?
Oxygen
Helium
Nitrogen
Carbon Dioxide
What is the chemical formula for carbon dioxide?
CO3
CO
CO2
C2O
How do you balance the equation: H2 + O2 → H2O?
2 H2 + 2 O2 → 2 H2O
2 H2 + O2 → 2 H2O
H2 + O2 → 2 H2O
H2 + O2 → H2O
What percentage of the air is made up of nitrogen?
90%
78%
85%
72%
What is the balanced equation for the reaction of hydrogen and oxygen to form water?
2 H2 + 2 O2 -> 2 H2O
2 H2 + O2 -> 2 H2O
H2 + 2 O2 -> 2 H2O
H2 + O2 -> H2O
Which gas is produced when fossil fuels are burned?
Carbon dioxide (CO2)
Oxygen (O2)
Nitrogen (N2)
Methane (CH4)
What is the main component of air that supports combustion?
Oxygen
Carbon Dioxide
Hydrogen
Nitrogen
How do you determine the number of atoms in a balanced chemical equation?
Count only the atoms in the reactants side of the equation.
Add the coefficients of the reactants and products together.
Count the total number of each type of atom on both sides of the balanced equation.
Multiply the number of molecules by their respective weights.
What is the approximate percentage of oxygen in the atmosphere?
21%
50%
30%
15%
What is the balanced equation for the reaction of sodium and chlorine to form sodium chloride?
Na + Cl -> NaCl
2Na + Cl2 -> 2NaCl
2Na + 2Cl -> NaCl2
Na2 + Cl2 -> 2NaCl
What gas is essential for human respiration?
Hydrogen
Oxygen
Nitrogen
Carbon Dioxide
How do you balance the equation: N2 + H2 → NH3?
N2 + H2 → 3NH3
N2 + 2H2 → NH3
N2 + 3H2 → 2NH3
2N2 + 6H2 → 4NH3
What is the role of argon in the atmosphere?
Argon is the primary component of the Earth's atmosphere.
Argon acts as a stable, inert gas in the atmosphere.
Argon is used to create weather patterns in the atmosphere.
Argon is a reactive gas that supports combustion.
