Complete the exercises below. a. Determine the number of sodium ions in the chemical formula of albite, NaₓAlSi₃O₈ b. Determine the number of hydroxide ions in the chemical formula of tremolite, Ca₂Mg₅(Si₄O₁₁)₂(OH)ₓ.

Verified step by step guidance

Step 1: Identify the chemical formula of albite, which is NaAlSi₃O₈. Notice that the subscript for sodium (Na) is 1, indicating there is one sodium ion per formula unit of albite.

Step 2: For tremolite, examine the chemical formula given: Ca₂Mg₅(Si₄O₁₁)₂(OH)ₓ. The subscript 'x' next to the hydroxide ion (OH) indicates the number of hydroxide ions present.

Step 3: Recognize that the chemical formula of tremolite is typically written as Ca₂Mg₅(Si₄O₁₁)₂(OH)₂, meaning there are 2 hydroxide ions per formula unit.

Step 4: Understand that the subscript 'x' in the problem is a placeholder for the actual number of hydroxide ions, which is 2 in the case of tremolite.

Step 5: Conclude that the number of sodium ions in albite is 1, and the number of hydroxide ions in tremolite is 2.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Chemical Formulas

Chemical formulas represent the composition of a compound, indicating the types and numbers of atoms present. In the case of albite, NaₓAlSi₃O₈, the subscript 'x' denotes the variable number of sodium ions, which can vary based on the specific mineral composition. Understanding how to interpret these formulas is essential for determining the number of specific ions in a compound.

Ionic Compounds

Ionic compounds are formed from the electrostatic attraction between positively charged ions (cations) and negatively charged ions (anions). In tremolite, Ca₂Mg₅(Si₄O₁₁)₂(OH)ₓ, the hydroxide ion (OH⁻) acts as an anion, and its quantity is determined by the overall charge balance of the compound. Recognizing the roles of cations and anions is crucial for analyzing the chemical formulas.

Charge Balance in Compounds

Charge balance is a fundamental principle in chemistry that states the total positive charge must equal the total negative charge in a neutral compound. For tremolite, the number of hydroxide ions (OH⁻) must be calculated to ensure that the overall charge of the compound is neutral. This concept is vital for determining the correct stoichiometry in ionic compounds.