Differences Between Elements, Compounds & Mixtures
Chemistry: Cambridge International GCSE Supplement, topic 2.1.1
Differences Between Elements, Compounds and Mixtures
Elements are pure substances. Compounds are chemically bonded atoms. Mixtures are physically combined substances which are easily separable.
What are elements?
- Elements are pure substances made of only one type of atom.
- The element gold contains only gold atoms.
- Elements cannot be broken down into simpler substances by chemicals.
- Dmitri Mendeleev arranged elements in a table in 1869, which is now called the Periodic Table.
What are compounds?
- Compounds are substances made of two or more different atoms chemically bonded.
- Water (H2O) is a compound made from hydrogen and oxygen atoms.
- Compounds have fixed proportions of elements.
- Compounds can be broken down into elements by chemical reactions.
- Compounds have properties different from elements that make them.
What are mixtures?
- Mixtures contain two or more substances that are not chemically joined.
- Air is a mixture of gases like oxygen and nitrogen.
- Mixtures can have any amount of each substance.
- Mixtures can be separated by physical methods.
- For example, filtration or evaporation.
- Mixtures keep the properties of their components.
Differences summary
- Elements have one type of atom; compounds have chemically joined atoms; mixtures have physically combined substances.
- Elements and compounds are pure; mixtures are not.
- Elements cannot be separated; compounds separate by chemical means; mixtures separate by physical means.
- Compounds have fixed ratios; mixtures have variable amounts.
Test yourself on Differences Between Elements, Compounds & Mixtures
What is an element?
Which of the following statements correctly highlights a difference between elements, compounds, and mixtures?