(a) What is the mass, in grams, of one mole of ¹²C?

Verified step by step guidance

1. Understand that the mass of one mole of an element is its molar mass, which is numerically equal to the atomic mass of the element in atomic mass units (amu).
2. Recognize that the atomic mass of carbon-12 (\(^{12}\text{C}\)) is exactly 12 amu by definition.
3. Recall that one mole of any substance contains Avogadro's number of entities, which is approximately \(6.022 \times 10^{23}\) entities.
4. Since the atomic mass of \(^{12}\text{C}\) is 12 amu, the molar mass of \(^{12}\text{C}\) is 12 grams per mole.
5. Conclude that the mass of one mole of \(^{12}\text{C}\) is 12 grams.

Key Concepts

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is numerically equivalent to the atomic or molecular weight of the substance in atomic mass units (amu). For example, the molar mass of carbon-12 (12C) is 12 g/mol, meaning one mole of carbon-12 weighs 12 grams.

Avogadro's Number

Avogadro's number, approximately 6.022 x 10²³, is the number of atoms, molecules, or particles in one mole of a substance. This constant allows chemists to convert between the number of particles and the amount of substance in moles, facilitating calculations in stoichiometry and chemical reactions.

Isotopes

Isotopes are variants of a chemical element that have the same number of protons but different numbers of neutrons, resulting in different atomic masses. Carbon-12 is a stable isotope of carbon with 6 protons and 6 neutrons, and it is commonly used as a standard for defining the mole and molar mass in chemistry.