Equilibrium in BiCl3 hydrolysis solution Steps:

• Calculate initial moles of BiCl3: 19.57 g ÷ 315 g mol⁻¹ ≈ 0.062 mol.
• Initial concentration: 0.062 mol ÷ 0.5 dm³ ≈ 0.124 mol dm⁻³, approximated as 0.1 mol dm⁻³ at equilibrium after partial reaction.
• Statement 2 holds by definition of dynamic equilibrium, where forward and reverse rates are equal.
• Statement 3 follows Le Chatelier's principle: added HCl increases product concentration, shifting equilibrium left to consume excess HCl.

Why A is correct:

• Includes all statements: 1 uses calculated/approximated equilibrium [BiCl3], 2 defines equilibrium rates, 3 applies Le Chatelier's principle to reversible reaction.

Why the others are wrong:

• B excludes 3, but adding HCl shifts equilibrium left.
• C excludes 2, but rates equalize at equilibrium.
• D excludes 1, but equilibrium [BiCl3] ≈ 0.1 mol dm⁻³.

Final answer: A