UNIT 7 MATTER AND MATERIALS
CONTENIDOS
Propiedades y estados de la materia Los cambios de la materia Los materiales y sus propiedades Diferentes usos de los materiales en función de sus propiedades. Los materiales y la sociedad Medimos la masa y el volumen de los cuerpos
CRITERIOS DE EVALUACION
Conoce las propiedades fundamentales de la materia Describe oralmente los cambios que sufren algunos materiales, oxidación, sequedad, cambio de tamaño, color, propiedades y estado, tras la exposición a agentes ambientales Explica con ejemplos concretos y familiares la relación entre las características de algunos materiales y los usos a los que se destinan Relaciona distintos tipos de materiales, en función de sus propiedades particulares, con su uso y época de utilización
UNIT 4: MATTER AND MATERIALS WHAT CAN WE FEEL WITH OUR SENSES? MATTER
MATERIALS Where do materials come from?
What are the states of matter?
SOLIDS
LIQUIDS
GAS
Natural materials
Hand-made materials
Come from What are the general properties of solids?
Definite volumen Definite shape
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What are the general properties of liquids?
Definite volumen Take the shape of its container
What are the general properties of gases?
animals Expand Take the shape and volumen of its container
Leather Wool
plants Rubber Wood Cotton clay
Paper Fabrics Petroleum derivatives
1.- MATTER. Matter is everything that occupies space and has got mass and volume. Rocks, water, air, the stars, living organisms and all objects are made of matter.
Matter has two properties: mass and volume.
But not everything is made of matter. Light and heat are not matter.
2.- MASS.
The mass of an object is a measure of how much matter it consists of. To find out the mass of an object we use instruments called
scales.
A kilogram is a unit of mass.
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3.- VOLUME.
The volume of an object is how much space it occupies. We can measure volume by using measuring containers. A
liter
is
a unit of volume.
4.- PURE SUBSTANCES AND MIXTURES.
In nature, matter can be a pure substance or a mixture.
Pure substances are formed from just one type of matter, such as salt, water and oxygen .
Mixtures Mixtures are formed from various components or various types of matter. For example, salt water is a mixture of water and salt. Air and honey are also mixtures. Sometimes you can see the different components in a mixture and sometimes you can´t.
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5.- MATTER IN DIFFERENT STATES. Matter can be found in three states: solid, liquid or gas.
SOLIDS Ice, iron, glass and stone are matter in a solid state. A solid has got a definite shape and volumen which doesn´t change unless we use force or heat on it.
LIQUIDS Water, oil, vinegar and honey are matter in a liquid state. It is a state of matter in which a substance has a definite volume but takes the shape of its container.
GASES Water vapor, oxygen, carbon dioxide and butane are gases. It is a state of matter in which a substance takes both the shape and the volume of its container.
MATTER CAN CHANGE
Matter can change if we treat it with force or if we heat it or cool it. Two important changes to matter are changes of state and combustion.
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CHANGES OF STATE Matter can change state if we heat it or cool it. Let´s look at water. Water in a solid state is called ice. When ice is heated it melts and becomes liquid water. If we heat water, it becomes a gas called water vapor.
COMBUSTION Combustion is a chemical reaction that happens when something burns. Three things are necessary for combustion to occur :
Fuel. This is a material that can burn. For example, wood, coal, gasoline and butane.
Something to start the combustion. This could be a spark, heat, or another object that is already burning.
Oxygen. During combustion, the fuel combines with oxygen. Together they change into other materials, such as ash, water vapor and gases like carbon dioxide. Combustion produces light and heat.
Combustion is a chemical reaction that happens when something burns. For combustion it is necessary: fuel, something to start the combustion and oxygen . Combustion produces light and heat.
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6.-HOW WE USE MATERIALS. When matter has particular properties, we call it a material. We use different materials because their properties are useful to us. Materials can be natural or man-
made. NATURAL MATERIALS : water, wood, tree resins, natural fibers, animal skins, stone and minerals, coal, petroleum and natural gas
We use water to clean, to cool and to put out fires.
Wood is resistant and flexible. We use it to make furniture.
Tree resins are sticky. We use them as glue.
Natural fibers are vegetable fibers like cotton and animal fibers like wool. We use them to make fabric.
Animal skins are flexible and keep out the cold. We use them to make clothes and shoes.
Stone and minerals are used to build houses and make jewelry.
We use coal, petroleum and natural gas to produce light and heat.
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MAN-MADE MATERIALS Man-made materials are produced by transforming natural materials. Paper, glass, gasoline are examples of man-made materials.
We produce metals from certain minerals. They are strong, hard, shiny and flexible. We make paper with crushed wood, water and resin. Glass is made by melting sand and mixing it with certain metals. It´s a very hard material and usually transparent. We use petroleum derivatives to make various materials: Plastic is waterproofed, insulating and flexible. Synthetic fibers like nylon and polyester make very strong and durable fabrics. Gasoline is made from petroleum. We use it as fuel for engines.
QUESTIONS 1. - Match the words to their definitions. Ceramic---clay---concrete---glass---metal Mud---paper---plastic---tiles a) A flexible material we write and draw on. b) A hard, grey material used for walls, floors and paths. c) A soft material that can be heated to make it hard. d) A hard, transparent material. e) A hard material we use to make cups and bricks. f) A strong material that we use to make cars. g) Hard, flat pieces that we put on kitchen and bathroom walls. h) We use it to make water bottles and lunchboxes. i) This is a sticky mixture of earth and water. 2. - What is matter?
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3. - Match the vocabulary below to the definitions. a) Kilograms a) the amount of matter something is made of. b) Liters b) an instrument for measuring mass. c) Mass c) a unit of volume d) Measuring container d) the space that something occupies. e) Scales e) an object used for measuring volume. f) Volume f) a unit of mass. 4. - What is a pure substance? And What is a mixture? 5. - Sort the words into pure substances and mixtures. Air honey iron oxygen salt Salt water water 6. - Can you always see the different components in a mixture? 7. - What are the three states of matter? 8. - Write some examples of solids, liquids and gases. Draw them. 9. - Are these sentences True or False? Correct the false ones. a) Matter can be found in two states: solid or gas. b) A solid never changes its shape. c) A liquid takes the form of whatever contains it. 10. - Name a white liquid that you can drink. 11. - Which is the odd one out and why? Bread honey olive oil Glass iron rain
vinegar stone
12. - Can you guess which gases are they? Oxygen butane carbon dioxide water vapor a) You will see this gas if you boil water. b) Plants need this gas for photosynthesis. c) This gas is in the air we breathe. d) This gas is used for cooking and for hot water boilers. 13. - Choose the correct answers: a) Gas can be/cannot be contained inside an open container. b) When you boil water you get oxygen/water vapor.
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17. - Choose the correct answer to complete the sentences. a) If you heat butter in a frying pan it becomes a liquid/a solid. b) If you put milk in the freezer it becomes a gas /a solid. c) When ice melts it becomes a gas/a liquid. d) When you heat water it becomes a solid/a liquid. e) When water vapor cools it becomes a solid/a liquid. f) When water freezes it becomes a solid/a gas. 18. - Match the words to their definitions. a) Ash b) a small bright flash of energy or light b) Combustion b) hot red and yellow light c) Flames c) the black and grey dust that burnt material becomes d) Fuel d) a chemical reaction that happens when something burns e) Spark e) a material that can burn 19. - Write down six natural materials we can use. 20. - Write down six man-made materials we can use.
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