Silver chloride, often used in silver plating, contains 75.27% Ag by mass. Calculate the mass of silver chloride required to plate 123 mg of pure silver.

Verified step by step guidance

1. Identify the percentage of silver (Ag) in silver chloride (AgCl), which is given as 75.27%.
2. Recognize that the percentage by mass means that in 100 g of AgCl, there are 75.27 g of Ag.
3. Set up a proportion to find the mass of AgCl needed to obtain 123 mg of Ag. Use the relationship: (mass of Ag / mass of AgCl) = 75.27 / 100.
4. Rearrange the proportion to solve for the mass of AgCl: mass of AgCl = (mass of Ag * 100) / 75.27.
5. Substitute the given mass of Ag (123 mg) into the equation to find the mass of AgCl required.

Key Concepts

Mass Percent Composition

Mass percent composition is a way to express the concentration of an element in a compound, calculated as the mass of the element divided by the total mass of the compound, multiplied by 100. In this case, knowing that silver chloride (AgCl) contains 75.27% silver by mass allows us to determine the relationship between the mass of silver and the mass of silver chloride needed for plating.

Stoichiometry

Stoichiometry is the area of chemistry that deals with the quantitative relationships between the reactants and products in a chemical reaction. It allows us to convert between grams of one substance and grams of another using their molar masses. In this problem, stoichiometry helps us calculate how much silver chloride is required to provide a specific mass of silver.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). For silver chloride, the molar mass is the sum of the atomic masses of silver and chlorine. Understanding molar mass is essential for converting between mass and moles, which is necessary for solving the problem of how much silver chloride is needed to plate a given mass of silver.