How many moles of anions are in 35.6 g of AlF3?

Verified step by step guidance

1. Identify the chemical formula of the compound: \( \text{AlF}_3 \).
2. Determine the molar mass of \( \text{AlF}_3 \) by adding the atomic masses of Al and F. Use the periodic table to find: Al = 26.98 g/mol and F = 19.00 g/mol.
3. Calculate the molar mass of \( \text{AlF}_3 \): \( 26.98 + 3 \times 19.00 \).
4. Convert the given mass of \( \text{AlF}_3 \) (35.6 g) to moles using the formula: \( \text{moles} = \frac{\text{mass}}{\text{molar mass}} \).
5. Since each formula unit of \( \text{AlF}_3 \) contains 3 fluoride anions (F\(^-\)), multiply the moles of \( \text{AlF}_3 \) by 3 to find the moles of anions.

Key Concepts

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). To find the molar mass of a compound, you sum the atomic masses of all the atoms in its formula. For aluminum fluoride (AlF3), the molar mass is calculated by adding the molar mass of aluminum (Al) and three times the molar mass of fluorine (F).

Stoichiometry

Stoichiometry is the area of chemistry that deals with the relationships between the quantities of reactants and products in a chemical reaction. It allows us to convert between grams, moles, and molecules using the coefficients from a balanced chemical equation. In the case of AlF3, understanding the stoichiometry helps determine the number of moles of anions (F-) produced from a given mass of the compound.

Ionic Compounds

Ionic compounds are formed from the electrostatic attraction between positively charged cations and negatively charged anions. In AlF3, aluminum (Al) acts as a cation with a +3 charge, while fluorine (F) acts as an anion with a -1 charge. Each formula unit of AlF3 contains three fluoride ions for every aluminum ion, which is crucial for calculating the total number of moles of anions present in a given mass of the compound.