Chemistry: Stoichiometry

What is the SI unit for the amount of substance, defined as containing exactly 6.02214076 × 10^23 elementary entities?

The mole (mol).

What constant represents the number of constituent particles (usually atoms or molecules) per mole of a substance?

Avogadro's number (N_A).

What term describes the mass of one mole of a chemical element or chemical compound, usually expressed in g/mol?

Molar mass.

According to the Law of Conservation of Mass, why must chemical equations be balanced?

Matter cannot be created or destroyed in a chemical reaction; the number of atoms of each element must remain constant.

What is the simplest whole-number ratio of atoms of each element present in a compound?

Empirical formula.

What is the maximum amount of product that can be produced from a given amount of reactant, based on stoichiometric calculations?

Theoretical yield.

How do you calculate the number of moles (n) if you are given the mass (m) and the molar mass (M) of a substance?

n = m / M.

In the balanced reaction 2H2 + O2 -> 2H2O, what is the mole ratio of oxygen gas to water produced?

1:2 (one mole of O2 produces two moles of H2O).

If the actual yield of a reaction is 45 grams and the theoretical yield is 50 grams, what is the percent yield?

90%.

What is the first step in identifying the limiting reagent when given the masses of two different reactants?

Convert the masses of both reactants into moles using their respective molar masses.