Calculate the mass percent composition of each of the following substances. (a) Malachite, a copper-containing mineral: Cu₂(OH)₂CO₃

Key Concepts

Molar Mass Calculation

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). To calculate the molar mass of a compound, you sum the atomic masses of all the atoms in its chemical formula. For malachite, Cu₂(OH)₂CO₃, you would calculate the molar mass by adding the contributions from copper (Cu), oxygen (O), hydrogen (H), and carbon (C) based on their respective quantities in the formula.

Mass Percent Composition

Mass percent composition refers to the percentage by mass of each element in a compound. It is calculated by dividing the mass of each element in one mole of the compound by the total molar mass of the compound, then multiplying by 100. This concept is essential for understanding the distribution of elements within a compound and is particularly useful in stoichiometry and chemical analysis.

Chemical Formula Interpretation

Interpreting a chemical formula involves understanding the types and numbers of atoms present in a compound. In the case of malachite, Cu₂(OH)₂CO₃, the formula indicates that there are two copper atoms, two hydroxide groups (OH), one carbonate group (CO₃), and the associated oxygen and hydrogen atoms. This interpretation is crucial for accurately calculating both the molar mass and the mass percent composition of the compound.