A mixture is a material composed of two or more simpler substances in chemistry.

A mixture is a material composed of two or more simpler substances in chemistry.

1. Chemistry – States of Matter Mixtures

2. To define a mixture and state examples. To compare mixtures to compounds. To model air as a mixture. To understand how mixtures look at a particle level. Learning Objective Success Criteria

3. Starter Is making a salad a chemical reaction or physical change, or both?

4. You might chop ingredients for a salad. For example, lettuce leaves. The atoms inside of them have not been re-arranged. So we call this a physical reaction. Making a Salad

5. You might heat substances for a salad. For example, boiling an egg. The atoms inside of them have been re-arranged. So we call this a chemical reaction. Photo courtesy of ProjectManhattan , via Wikimedia Commons Making a Salad

6. When you eat a mixed salad, the ingredients mostly keep their individual taste . So, we say their properties have stayed the same . Remember in science, the word properties means features or characteristics, not houses or buildings! Making a Salad

7. Iron filings are small, grey pieces of metal. Solid sulfur is a yellow powder. Watch as we mix them. Is this a chemical reaction or physical change? Photo courtesy of oskay , via Flickr Mixtures vs Compounds: Demonstration

8. Iron filings are small, grey pieces of metal. Solid sulfur is a yellow powder. Watch as we heat them. Photo courtesy of oskay , via Flickr Is this a chemical reaction or physical change? Mixtures vs Compounds: Demonstration

9. When the iron filings and sulfur powder were stirred together, you could easily separate them with a magnet. They still had their own individual colour and properties . The atoms had not been re-arranged . So this was a physical change. Photo courtesy of Asoult , via Wikimedia Commons Mixtures vs Compounds: Demonstration

10. When the iron filings and sulfur powder were heated together, you could not separate them with a magnet. The yellow colour disappeared and a dark metal solid was formed, with different properties . The atoms had been re-arranged and bonded together . So this was a chemical reaction. Mixtures vs Compounds: Demonstration

11. A mixture contains ___________ or more substances that are not ___________ joined together (b ___________ ). The substances keep their own ___________ . You can (usually) easily __________ them using __________ methods. Mixtures: Definition

12. A mixture contains ___________ or more substances that are not ___________ joined together (b ___________ ). The substances keep their own ___________ . You can (usually) easily __________ them using __________ methods. Key Words : physical, bonded, chemically, two, separate, properties. Mixtures: Definition

13. A mixture contains t__________ or more substances that are not c__________ joined together (b ___________ ). The substances keep their own pr ___________ . You can (usually) easily s __________ them using ph ________ methods. Key Words : physical, bonded, chemically, two, separate, properties. Mixtures: Definition

14. A mixture contains two or more substances that are not chemically joined together ( bonded ). The substances keep their own properties . You can (usually) easily separate them using physical methods. Challenge : Can you make your own definition of a compound using the same structure above? Mixtures: Definition

15. A compound contains two or more elements that are chemically joined together ( bonded ). A compound has different properties to it’s individual elements. You can separate them using chemical reactions. Compounds: Definition

16. Look at each picture. In pairs, can you guess which are elements, compounds or mixtures? Picture A Ne Ne Ne Ne Picture B N N O O O C O Picture C N N N N N N N N Picture D O O H O O H Challenge : Can you name any of these elements, compounds or mixtures? Identifying Activity

17. Picture A Ne Ne Ne Ne Picture B N N O O O C O Picture C N N N N N N N N Picture D O O H O O H Look at each picture. In pairs, can you guess which are elements, compounds or mixtures? element (neon) mixture (air) element (nitrogen) compound (water) Identifying Activity: Answers

18. Air as a Mixture Picture B represented some of the main parts of air. Within the mixture of air, there are also elements and compounds. Can you identify them? Picture B N N O O O C O

19. Picture B represented some of the main parts of air. Within the mixture of air, there are also elements and compounds. Can you identify them? Picture B N N O O O C O Oxygen and nitrogen are elements. Carbon dioxide is a compound. Fascinating Fact! Some atoms exist in pairs, like oxygen and nitrogen. We call these ‘ diatomic ’ from the Greek word for ‘two’ or ‘double’. Air as a Mixture

20. seawater mud concrete water - and - oil By Victor Blacus , via Wikimedia Commons More Mixtures

21. In pairs, take it in turns to explain why each of the four examples on the left are mixtures. Score your friends answers out of ten based on: how many keywords they used; whether they used their notes to help. seawater mud concrete water and oil By Victor Blacus , via Wikimedia Commons Explanation Activity

22. Alloys are substances made up of at least one metal, sometimes two, to give greater strength or lower melting points. Nitinol is made from nickel and titanium. It is used in the frames of glasses as when this metal is bent out of shape, you can use heat to return it to the original shape! By Petermaerki , via Wikimedia Commons Plenary: Alloys

23. Here is a basic picture of the particles inside of nitinol (made from nickel and titanium). Is nitinol an element, compound or mixture? Explain your answer. Ni Ni Ni Ti Ti Ti Ni Ni Ni Ti Ti Ti Ni Ni Ni Ti Ti Ti Plenary: Alloys

24. I can define a mixture and state examples. I can compare mixtures to compounds. I can model air as a mixture. What Did You Achieve Today?