U06 Stoichiometry

Front

What is stoichiometry?

Back

Stoichiometry is the branch of chemistry that deals with the calculation of reactants and products in chemical reactions based on the conservation of mass.

Front

What is a mole in chemistry?

Back

A mole is a unit of measurement used to express amounts of a chemical substance, defined as exactly 6.022 x 10²³ particles (atoms, molecules, etc.).

Front

What does the term 'limiting reactant' mean?

Back

The limiting reactant is the substance that is completely consumed in a chemical reaction, limiting the amount of product that can be formed.

Front

How do you determine the limiting reactant in a reaction?

Back

To determine the limiting reactant, calculate the number of moles of each reactant and compare the mole ratios from the balanced equation.

Front

What is the balanced equation for the reaction of aluminum and oxygen?

Back

4 Al + 3 O₂ → 2 Al₂O₃.

Front

If 6 moles of H₂ are used, how many moles of O₂ are needed in the reaction 2H₂ + O₂ → 2H₂O?

Back

3 moles of O₂ are needed.

Front

What is the mole ratio of H₂ to H₂O in the reaction 2H₂ + O₂ → 2H₂O?

Back

The mole ratio is 2:2 or 1:1.

Front

How many grams of O₂ are in 2 moles of O₂? (Molar mass of O₂ = 32 g/mol)

Back

64 grams of O₂.

Front

What is the purpose of a balanced chemical equation?

Back

A balanced chemical equation ensures that the number of atoms for each element is conserved during the reaction.

Front

In the reaction 4NH₃ + 6NO → 5N₂ + 6H₂O, how many moles of N₂ are produced from 10 moles of NH₃?

Back

12.5 moles of N₂ are produced.