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A deep dive into the H2O molecule to see how hydrogen and oxygen work together.
Did you know that every single drop of water in your glass is made of billions of tiny 'Mickey Mouse' shapes that are far too small for your eyes to see?
Everything in our world is built from tiny building blocks called atoms. Imagine atoms are like different colors of LEGO bricks. To build a single molecule of water, you need two specific types of 'bricks': Hydrogen and Oxygen. Oxygen is a slightly larger atom, while Hydrogen is the smallest atom in the entire universe! When these atoms join together, they create the liquid we drink, bathe in, and swim in every day.
Quick Check
What are the two types of atoms that join together to make a water molecule?
Answer
Hydrogen and Oxygen.
Scientists use a special 'secret code' called a chemical formula to describe what things are made of. For water, that code is . The letters tell us which atoms are inside: stands for Hydrogen and stands for Oxygen. The little number is called a subscript. It tells us exactly how many of the atom before it are in the molecule. So, means there are Hydrogen atoms. Since there is no number after the , it means there is just Oxygen atom.
Let's look at one single molecule of : 1. Look at the : The subscript tells us we have Hydrogen atoms. 2. Look at the : No number means we have Oxygen atom. 3. Total atoms: atoms in one water molecule.
Quick Check
In the formula , what does the little number 2 tell us?
Answer
It tells us there are 2 Hydrogen atoms in the molecule.
Atoms don't just float near each other; they stick together in a very specific shape. In a water molecule, the large Oxygen atom sits in the middle. The two smaller Hydrogen atoms attach to the top of the Oxygen at an angle. This makes the molecule look like a head with two round ears! Because of this, scientists often say water molecules look like Mickey Mouse. This 'bent' shape is very important because it helps water molecules stick to each other, which is why water forms round drops on a window.
If you had water molecules, how many total atoms would you have? 1. Each molecule has Hydrogen atoms. So, Hydrogen atoms. 2. Each molecule has Oxygen atom. So, Oxygen atoms. 3. Total atoms: atoms total.
Imagine you are building a model using clay balls and toothpicks: 1. Pick a large red ball for Oxygen. 2. Pick two smaller white balls for Hydrogen. 3. Stick the toothpicks into the Oxygen ball so they point up and out, like the letter 'V'. 4. Attach the Hydrogen balls to the ends. You have now modeled the 'bent' structure of !
What does the 'H' stand for in ?
How many total atoms are in one single molecule of water?
A water molecule is shaped like a straight line.
Review Tomorrow
Tomorrow morning, try to remember the 'secret code' for water and name the two types of atoms that make it up.
Practice Activity
Draw a picture of a water molecule. Color the Oxygen atom red and the two Hydrogen atoms blue. Label them to show you know which is which!