Natural or synthetic?
Find out where eleven everyday materials come from, from Dhaka cloth and pashmina to nylon and plastic bags, test a thread of each in a flame, and sort them into natural and synthetic.
Core concept
Natural materials come from plants, animals or the ground; synthetic materials are made in factories, mostly from petroleum, and behave differently when burnt and in the soil
Topic: Materials in daily life
The things we use every day are made of many materials. Some are natural: cotton and jute come from plants, wool, silk and leather from animals, and bamboo grows in our hills. Others are synthetic: they are made in factories by people, mostly from petroleum (crude oil). Nylon, polyester, acrylic and the plastic of bags and thermocol are synthetic. A burn test on a single thread can tell them apart: plant fibres burn like paper, animal fibres smell like burning hair, and synthetic fibres shrink and melt into a hard bead. Natural materials rot away in the soil, but most synthetic ones last for hundreds of years.
What you will learn
- Classify everyday materials as natural or synthetic.
- Say whether a natural material comes from a plant or an animal.
- Describe how a burn test tells plant, animal and synthetic fibres apart.
- Explain why synthetic materials such as plastic bags harm the environment.
Before you start
- Name some everyday materials, such as cotton, wool and plastic.
Materials
- Threads or small pieces of cotton, jute, bamboo, wool, silk, leather, nylon, polyester, acrylic, a plastic bag and thermocol
Equipment
- Tongs, a candle, a metal tray, a bucket of water or sand
Procedure
- Pick a material card and find out where it comes from.
- Do a burn test on a thread of at least six materials.
- Sort every material into natural or synthetic.