A 0.30 M solution of AlCl3 contains?

Each mole of AlCl₃ contains 1 mole of Al³⁺ ions and 3 moles of Cl⁻ ions.

In 0.30 M solution of AlCl₃ :
Molarity of Al³⁺ ions = (0.30 M) × 1 = 0.30 M
Molarity of Cl⁻ ions = (0.30 M) × 3= 0.90 M

The answer: e. 0.30 M Al³⁺ ions and 0.90 M Cl⁻ ions.

AlCl3 solution....

The subscripts in a chemical formula tell the number of moles of each element in one mole of the compound.

A 0.30M solution will contains 0.30 moles per liter of Al^3+ ions and 0.90 moles per liter of Cl^- ions.

Assuming you have 1.0 L of 0.30M solution, then 'e'.

When one mole of aluminum chloride is dissolved in water, one mole of aluminum ions and three moles of chloride ions are formed. 0.30 M means 0.30 mole of aluminum chloride is dissolved in one liter of water.

Number of moles of Al+3 = 0.30
Number of moles of Cl-1 = 0.90
Letter e is the correct answer.