What Are Atoms?

Before we learn how to count atoms, let’s understand what atoms are. Atoms are the building blocks of everything around us.
They are tiny particles that make up all matter in the universe. Imagine atoms as the LEGO bricks of nature, joining together
to form molecules and substances.

Each atom is made up of even smaller particles called protons, neutrons, and electrons. Protons have a positive charge, neutrons
carry no charge, and electrons have a negative charge. These subatomic particles determine the properties of different atoms.

Atomic Number and Atomic Mass

Now, let’s introduce two crucial concepts in the world of atoms: atomic number and atomic mass. The atomic number of an atom
tells us the number of protons in its nucleus. For example, hydrogen has an atomic number of 1, which means it has one proton.

On the other hand, the atomic mass of an atom is the sum of its protons and neutrons. This value gives us the total mass of the
atom. For oxygen, which has 8 protons and 8 neutrons, the atomic mass is 16.

Counting Atoms in a Molecule

Now, let’s move on to the exciting part: counting atoms in a molecule. A molecule is a group of atoms bonded together. To count
atoms in a molecule, we need to look at the chemical formula. A chemical formula shows the types and numbers of atoms present in
a compound.

Let’s take a simple molecule like water, which has the chemical formula H2O. This formula tells us that water consists of 2 hydrogen
atoms and 1 oxygen atom. The numbers next to the elements indicate how many atoms of each element are present in the molecule.

Rules for Counting Atoms

There are some rules we need to follow when counting atoms in a molecule:

• Subscripts: The small numbers written to the right of the element symbol indicate the number of atoms of that
  element. For example, in CO2, there are 2 oxygen atoms.
• Parentheses: Parentheses are used to group atoms together. The number outside the parentheses applies to all
  atoms inside. For example, (NH4)2SO4 contains 2 ammonium groups and 1 sulfate group.
• Coefficients: Coefficients outside the chemical formula apply to all the atoms inside. If there is no subscript
  after an element, it means there is one atom of that element.

Practice Makes Perfect

Let’s put our atom-counting skills to the test with some practice exercises:

Exercise 1: Counting Atoms in Carbon Dioxide (CO2)

How many oxygen atoms are in one molecule of carbon dioxide?

Exercise 2: Counting Atoms in Ammonium Bicarbonate ([NH4]HCO3)

How many hydrogen atoms are present in one molecule of ammonium bicarbonate?

Try solving these exercises on your own and compare your answers with a friend or a teacher. Remember, practice leads to perfection!

Congratulations, young scientists! You have now learned the basics of counting atoms in molecules. Remember, atoms are the fundamental
units of matter, and understanding how they combine to form compounds is the key to unlocking the secrets of chemistry.

Keep exploring the fascinating world of atoms, and who knows, you might make groundbreaking discoveries one day. Happy atom counting!