1. WHAT IS MATTER? Matter is everything that has mass andvolume. The different types of matter are calledsubstances. Ex: iron, oil.
SOLIDS LIQUIDS GASESThey havefixed volume.They have aconstant volume.They don’t havefixed volume.They havefixed shape.They don’t have ashape.They can flow.They don’t havefixed shape.They canexpand.The particlesare very closetogether.The particles areless closetogether thansolids.The particles arefar apart fromeach other.2. THE STATES OF MATTER
3. CHANGE OF STATE The heat separates and disperses the particles.a) Solid to liquid: Fusion.b) Liquid to solid: Solidification.c) Liquid to gas: Evaporation.d) Gas to liquid: Condensation.e) Solid to gas: Sublimationf) Gas to solid: Inverse sublimation or deposition.
4. ATOMS AND MOLECULES All matter is made up of very tiny particles calledatoms. Atoms are the smallest part of any substance. Atoms are made up of: A nucleus: protons (+) and neutrons.(0) Electrons (-) around the nucleus. Examples: Oxygen, iron, nitrogen, etc. Atoms join together to form molecules. Ex: CO2(Carbon dioxide), O3 (Ozone), H2O (water)
5. ELEMENTS AND COMPOUND Elements are substances formed by atoms of a singletype. There are 118 elements. It is represented by a chemical symbol included inthe periodic table. Example: Carbon (C) Compounds: There are two or more different atoms joinedtogether. Ex: Salt (NaCl), water (H2O)Element SymbolElement Name
6. PURE SUBSTANCES AND MIXTURES Pure substances are formed by similar particles(atoms or molecules). Ex: iron or sugar. Mixture is the physical combination of two or morepure substances. Types: Homogeneus mixture (solution): The substances can’tbe identified. Ex: sea water, wine, chocolate. Heterogeneus mixture: The substances can beidentified. Ex: water and oil, soup, orange juice. Some methods for separating mixtures are magneticseparation, decantation, crystallization and filtration.
ACTIVITIES1. What is matter?2. What is a substance?3. State which of the following are matter: beauty,water, liberty, trees, paper, glass, sadness.4. Make a grid and classify the following thinginto solid, liquid or gas: rocks, river water, the airwe breath, ice, milk, a fork, an orange juice.5. Why does the physical state of a substancechange?6. The temperature of an imaginary substance atfusion is 20ºC.a) What state is that substance in if the roomtemperature is 25ºC?b)And if the temperature is 15ºC?
7. Match the two columns. (The items on the left canbe matched to one or more of the items on the right)a) Atom 1. Feb) Chemical element 2. CH4c) Compound 3. Mgd) Molecules 4. N28. The formula of methane is CH4.What types ofatoms are there in this compound? How many ofeach type?9. Draw a nitrogen (N2) and an ammonia (NH3) withcoloured balls. Use a different colour for eachtype of atom.10. Make a list of five solutions used in daily life.11. Classify as pure substance or mixture: sugar,clouds, soup, aluminium.
12. Copy the two columns and match them:a) Constant shape and volume 1. Fusionb) Change from gas to solid 2. Gas statec) Constant volume and variable shape. 3. Solid stated) From solid to liquid. 4.Sublimatione) Variable volume and shape. 5. Liquid state13. let’s imagine you put some perfume. Why canpeople near you smell it? What is that propertycalled?14. Write the simbols for the following elements:iron, potasium, sodium, phosphorus, sulfur, carbon.15. Classify the following into two lists: elementsand compounds: Al, CH4, O2, CaCO3, S, H2
16. True or false? Correct the false sentences.a) Solutions are mixtures.b) Sea water and air are solutions.c) Cow’s milk is a pure substance.17. If we wash a glass and let the water drip, aftera while the glass will be dry. What has happenedto the water?