Revision of metals and non metals

04.22.2020
09:51:05
Dear students good morning
Today's revision concepts in unit 6 : everyday materials and their properties
Pg.no : 86 & 87
In Ur sciences course book grade 7
The important points are
1 . plastics -
* they are in different types,with different properties
* Some plastics are flexible,light weight and easily shaped
2. Fibres -
* Natural fibre - cotton ,silk
* Synthetic fibres ( made from chemicals)
Example polyster
* Fibres are tiny threads so they can be strong and bendy
3. Ceramics -
* It can withdraw High temperature
* They are hard, brittle and very strong.
* It is used in floor tiles,sinks etcc
* Glass is transparent and water proof.
* It can be recycled.
* It does not react with food or drink inside the jar.
* It is hard but very brittle.
No homework
For better understanding of concepts watch the below videos