Silver salts are used in black-and-white photography.Ag ions left in developing solutions are often collected by precipitation reactions.A 4.5 L bottle of a developing solution was treated with an excess of sodium chloride,and 2.86 g of dry silver chloride was collected.What was the molar concentration of the silver ions in the developing solution?

Question

Quizplus · Accepted Answer

The precipitated silver chloride was formed by reacting excess sodium chloride with the silver ions, so we can use the mass of silver chloride formed to calculate the moles of silver ions initially present in the solution:

Moles of Ag+ = Mass of AgCl / molar mass of AgCl
Moles of Ag+ = 2.86 g / 143.32 g/mol
Moles of Ag+ = 0.01997 mol

The developing solution had a volume of 4.5 L, so the molarity of the silver ions can be calculated as:

Molarity of Ag+ = Moles of Ag+ / Volume of solution
Molarity of Ag+ = 0.01997 mol / 4.5 L
Molarity of Ag+ = 0.00443 M

This corresponds to answer choice D) 4.4 M.

Silver Salts Are Used in Black-And-White Photography ×\times× 10-3 M C)2 ×\times×

Silver Salts Are Used in Black-And-White Photography $\times$ 10^-³ M
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