Question

Q1. A solution was prepared by dissolving a

Answer 1

Given, 5.761 0.002 g .

Molar mass of KCl.MgCl2.6H2O = 277.85 g/mol

Moles = Mass / Molar mass = 0.0207 mol

Each mol of KCl.MgCl2.6H2O contains 1 mol of K+ ion.

So, 0.0207 mol of KCl.MgCl2.6H2O contains 0.0207 mol

[K+] = 0.0207 mol / 3.000 = 0.0069 0.004 M

Each mol of KCl.MgCl2.6H2O contains 3 mol of Cl- ions.

So, 0.0207 mol of KCl.MgCl2.6H2O contains .0621 mol

[Cl-] = 0.0621 mol / 3.000 contians = 0.0207 0.004 M

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b)

pCl = -log [Cl-]

= -log [0.0207] log [0.004]

= 1.68 2.39