molecule
B1Pronunciation
UK
- /mˈɒlɪkjˌuːl/
US
- /ˈmɑləkˌjul/
Description
- tiny group of atoms
- bonded atoms
- very small unit of a substance
Imagine the air you breathe, the water you drink, and much of your own body being made from incredibly small pieces called molecules. A molecule forms when two or more atoms join together, like LEGO bricks clicking into place to make something bigger. Water (H₂O) is a simple molecule made of hydrogen and oxygen atoms. Different combinations of atoms make different kinds of molecules, and that helps give substances their own properties.
Think about baking a cake: you combine flour, sugar, and eggs to make something new. In a similar way, atoms join to make molecules. These tiny groups are always moving and interacting, and they are a big part of the materials and living things around us. From a drop of water to the cells in your body, molecules are everywhere.
A molecule is a group of two or more atoms held together by chemical bonds. It's the smallest unit of a chemical substance that retains its characteristic properties. Think of it like this: an atom is a single letter, and a molecule is a word formed from those letters. Just as different words have different meanings, different molecules have different characteristics.
Much of the world around us is made of atoms joined together. The oxygen we breathe usually does not exist as single oxygen atoms. Instead, it exists as O₂, two oxygen atoms bonded together in one molecule. In the same way, the sugar that sweetens your tea is made of carbon, hydrogen, and oxygen atoms arranged into larger molecules such as sucrose (C₁₂H₂₂O₁₁).
Molecules are incredibly diverse. Some are simple, like water (H₂O) or methane (CH₄). Others are enormous and complex, like the DNA molecule that carries our genetic code. These large molecules, called polymers, are made up of many repeating smaller units linked together – think of a long chain built from identical beads.
The study of molecules is central to chemistry and biology. Understanding how molecules interact allows us to create new materials, develop life-saving drugs, and better understand living things. So next time you look around, remember that many of the substances around you, from the air you breathe to the water you drink, are built from these tiny, active groups of atoms.
Examples
- 1
Chemistry
A water molecule is made of two hydrogen atoms and one oxygen atom.
- 2
Smell
When you smell coffee, tiny molecules are reaching your nose.
- 3
Medical research
Researchers are testing a new molecule that could be used in cancer treatment.
- 4
Detection
The sensor is sensitive enough to detect a single molecule.
- 5
Figurative amount
By the end of the week, she didn't have a molecule of energy left.
Pattern
not have a molecule of + noun
not have even a tiny amount
Forms and spellings
2 forms open this card.
Main spelling
- moleculenoun
Forms
- moleculespluralnoun