Table of contents

2. Atoms & Elements

Ions

Join thousands of students who trust us to help them ace their exams!Watch the first video

Multiple Choice

What must happen to an atom of magnesium in order to become a magnesium ion, Mg^{2+}?

It must lose two electrons.

It must gain two electrons.

It must gain two neutrons.

It must lose two protons.

Verified step by step guidance

Recall that an atom becomes an ion by gaining or losing electrons, which changes its charge but not its number of protons or neutrons.

Identify the charge of the magnesium ion given: Mg^{2+} means the ion has a positive charge of +2.

Since electrons carry a negative charge, losing electrons results in a positive charge on the ion.

Determine how many electrons must be lost to achieve a +2 charge: losing two electrons will give the atom a +2 charge.

Conclude that to become Mg^{2+}, a magnesium atom must lose two electrons.

Master Atoms vs. Ions with a bite sized video explanation from Jules

Problem sets built by lead tutors

Expert video explanations