Identifying and comparing materials Flashcards
Why is the handle of a saucepan made from plastic?
Saucepan handles are made from plastic because plastic is a poor conductor of heat, so you won’t get burned when you touch the handle.
Name the types of different materials
Metals
Plastics
Glass
Wood
Fabrics
What are the different properties of metals?
Most metals are strong, hard and shiny materials that can be hammered into different shapes without breaking. They are good
conductors
of heat and electricity and some are magnetic. Their properties make them useful for objects such as cutlery, saucepans, cars and coins.
What is an conductor?
A material which allows charge or heat to move easily through it.
What are the different properties of plastics?
Plastics are materials made from chemicals and are not found in nature. They are strong and waterproof. They can be made into any shape by applying heat. Plastics are not magnetic. They are good
insulators
and don’t conduct heat or electricity. They’re used to make things like bags, bottles and toys
What is an insulator?
insulator
A material that does not allow charge or heat to pass through it easily.
What are the different properties of glass?
Glass is made by melting sand and other minerals together at very high temperatures. It is normally
transparent
and can be made into different shapes. Thick glass can be strong, but thin glass breaks easily. It’s used for objects that need to be transparent, such as windows and spectacles.
What does transparent mean?
transparent
A material that we can see through, like glass, is transparent.
What are the different properties of wood ?
Wood comes from trees. It is strong, flexible and long-lasting. It is an insulator of heat and electricity. It’s used to make things such as furniture.
What are the different properties of fabrics ?
Fabrics are made from thin fibres woven together. Different fabrics have different properties. They can be stretchy (a pair of tights), insulating (a woollen coat) or
absorbent
(a towel). Fabrics are used to make clothes as they are flexible, warm and do not wear out easily.
What is the meaning of absorbent?
absorbent
Materials that soak up, or absorb, liquids are absorbent.
What is the meaning of Properties of materials?
Properties describe how a material behaves, and explain why it is well suited for a particular use. For example, metal has a high melting point (this is a property of most metals) so it is good to use to make a frying pan (this is the use of the material).
What does it mean when a material is hard?
Hard
A material is hard if you cannot easily scratch it. Lots of metals are hard – you cannot easily scratch a metal pair of scissors.
What does it mean when a material is transparent?
Transparent
A material is transparent if you can see through it. Glass is transparent. The opposite to transparent is opaque.
What does it mean when a material is a good thermal conductor?
Good thermal conductors
Metals are good thermal conductors because heat passes through them easily. Fabrics are poor thermal conductors.
What does it mean when a material is magnetic ?
Magnetic
Specific metals like iron and steel are magnetic because they can be attracted to a magnet.
What is a property of most metals?
Good electrical conductor
Which property of concrete explains why it is used to make road bridges?
It is strong
Name a property of most plastics?
Waterproof
Why is glass used to make windows?
It is transparent
Why would it NOT be a good idea to make a frying pan out of plastic?
It would melt or burn
Ways of separating substances
Sieving
Filtering
Evaporating
Explain SIEVING
sieving
A way of separating solid substances using a mesh called a sieve, which allows the smallest particles to pass through, but not the largest particles
Explain EVAPORATING
evaporating
When a liquid turns into a gas slowly, at temperatures below the boiling point.
Explain FILTERING
Filtering
A way of separating particles of a solid (e.g. sand) from a liquid (e.g. water).
When you separate a mixture of sand and water by passing it through a piece of
filter paper
. The water is able to pass through the tiny gaps in the paper but the sand particles are too big and are left on the surface of the filter paper. What is this process called?
Filtering
A mixture made of solid particles of different sizes, for example sand and gravel, can be separated by _________.
Sieving
How can water be separated from a salty solution?
Heating