Lesson 4 of 22
In Progress

Chapter 1 summary and exercises


An Oxygen Atom has eight positively charged sub-atomic particles in its nucleus.

Given that the number of neutrons in the Oxygen Atom is also eight.

  1. Determine the composition of the oxygen atom.
  2. Give the atomic mass of the oxygen atom in a.m.u.
  3. Write the nuclide representation of the oxygen atom.
  4. Calculate the charge of the nucleus in the oxygen atom.
  5. Deduce the charge of the electronic cloud.


The nucleus of an Atom Y contains 11 protons and 12 neutrons.

  1. Determine the number of elections of this atom.
  2. Calculate the elementary nuclear charge of the atom.
  3. Write the nuclide presentation of atom Y.
  4. Identify the elements that come directly before and after atom Y in the periodic table.
  5. Knowing that Atom X has 11 protons and 14 neutrons, identify if Atoms X and Y are Isotopes.
  6. Knowing that Atom Y loses 1 electron to becomes stable, determine the charge of the ion formed.