Ammonium sulfate, (NH₄)₂SO₄, is used in fertilizers to provide nitrogen for the soil. (7.1, 7.2) c. How many moles of ammonium sulfate contain 7.4 x 10²⁵ atoms of N?

A mole is a unit in chemistry that represents 6.022 x 10²³ entities, such as atoms or molecules. This number, known as Avogadro's number, allows chemists to convert between the mass of a substance and the number of particles it contains. Understanding moles is essential for quantifying chemical reactions and stoichiometry.

The chemical formula of a compound provides information about the types and numbers of atoms present. In ammonium sulfate, (NH₄)₂SO₄, there are two ammonium ions (NH₄⁺) contributing two nitrogen atoms and one sulfate ion (SO₄²⁻). Recognizing how to interpret chemical formulas is crucial for determining the composition of compounds and calculating moles.

Stoichiometry is the area of chemistry that deals with the relationships between the quantities of reactants and products in a chemical reaction. It allows for the calculation of moles of substances involved based on their ratios in a balanced equation. In this case, stoichiometry helps determine how many moles of ammonium sulfate correspond to a given number of nitrogen atoms.