Question

1.532 g of a mixture of nacl (m = 58.44 g mol-1) and kno3 (m = 101.10 g mol-¹) was dissolved in distilled water, and dilute nitric acid and agno3 solution were added until precipitation of agcl (m = 142.32 g mol-1) was complete. the residue was filtered off, washed and dried, and was found to have a mass of 2.943 g. how many moles of kno3 were in the original mixture?

Answer 1

The number of moles of KNO3 in the original mixture is 0.0207 mol.

Step-by-step explanation:

To find the number of moles of KNO3 in the original mixture, we need to first determine the number of moles of AgCl formed.

Given that the mass of the residue (AgCl) is 2.943 g, we can calculate the number of moles of AgCl using its molar mass (142.32 g/mol).

Moles of AgCl = Mass of AgCl / Molar mass of AgCl = 2.943 g / 142.32 g/mol = 0.0207 mol

Since the stoichiometry between AgCl and KNO3 is 1:1, the number of moles of KNO3 in the original mixture is also 0.0207 mol.