0973 03 Stoichiometry SUPPLEMENT

Front

How does the mass of the products of a chemical reaction compare to the mass of the reactants?

Back

The mass of the products of a chemical reaction is equal to the mass of the reactants

Front

How can the mass of a reactant in a chemical reaction be calculated when the masses of the other substances in the reaction are known?

Back

Subtract the sum of the known masses of any other reactants from the sum of the known masses of the products

Front

What is a mole?

Back

The amount of a substance that contains 6.02 x 10²³ particles (The type of particle depends on the substance it could be atoms, molecules or ions)

Front

What is the symbol for the unit mole?

Back

mol.

Front

What is the value of the Avogadro constant?

Back

6.02 x 10²³

Front

How does the number of particles in one mole of a substance compare to the number of particles in one mole of any other substance?

Back

They are equal

Front

What is the mass of one mole of any substance equal to?

Back

The substance’s relative formula mass (Mr), or relative atomic mass (Ar), in grams

Front

What do the numbers in front of substances in equations mean in terms of moles?

Back

How many moles of the substance are involved in the reaction

Front

What's the formula to work out the number of moles for a given mass of a substance?

Back

n=m/Mr . or . Mass of substance (g) ÷ relative formula mass (Mr)

Front

What's the formula to work out the mass of a substance for a given number of moles?

Back

m=n×Mr . or . Mass of substance (g) × relative formula mass (Mr)