Question

select all the true statements.
the cl⁻ and br⁻ ions have the same number of electrons.
anions carry a positive charge.
the cu⁺ and cu²⁺ ions have the same number of electrons.
when an atom gains an electron, it becomes a cation.
the k⁺ ion is formed when a potassium atom loses one electron.
the fe²⁺ and fe³⁺ ions have the same number of protons.

Explanation:

Step1: Analyze Cl⁻ and Br⁻ electrons

Chlorine (Cl) has 17 electrons, Cl⁻ has 18 electrons. Bromine (Br) has 35 electrons, Br⁻ has 36 electrons. So they don't have same number of electrons.

Step2: Define anions

Anions are negatively - charged ions. So they carry a negative charge, not positive.

Step3: Analyze Cu⁺ and Cu²⁺ electrons

Copper (Cu) has 29 electrons. Cu⁺ has 28 electrons and Cu²⁺ has 27 electrons. They don't have same number of electrons.

Step4: Define cations and anions

When an atom gains an electron, it becomes an anion. A cation is formed when an atom loses an electron.

Step5: Analyze K⁺ formation

Potassium (K) has 19 electrons. When it loses one electron, it forms K⁺ with 18 electrons. This statement is true.

Step6: Analyze Fe²⁺ and Fe³⁺ protons

Isotopes and ions of the same element have the same number of protons. Fe²⁺ and Fe³⁺ are ions of iron (Fe), so they have the same number of protons. This statement is true.

Answer:

The K⁺ ion is formed when a potassium atom loses one electron.
The Fe²⁺ and Fe³⁺ ions have the same number of protons.