In I/GCSE Chemistry, we will learn about Properties of Materials.
Synthetic Fibres – Nylon
Properties:
• Lightweight
• Tough
• Blocks ultraviolet light
Uses:
• Clothing
• Climbing ropes
Synthetic Fibres – Polyester
Properties:
• Lightweight
• Waterproof
• Tough
Uses:
• Clothing
• Bottles
Effectiveness
The properties of the materials used will affect the EFFECTIVENESS of the end product, so manufacturers always test and assess them carefully beforehand.
Refer to I/GCSE Chemistry, for example:
A pair of shoes made with leather uppers and a rubber sole would be most effective and durable:
LEATHER Is a waterproof and flexible; it can also be dyed in a range of colours, and can be given a shiny, polished surface.
RUBBER is also waterproof and flexible; it is very hard-wearing, and will not slip easily when in contact with the ground.
Data
Many people may have ideas about why materials have different properties, but these opinions are not very useful if they are not supported by DATA. To justify an explanation, you need to have data to support it, This data may be obtained by taking measurements.
For Example: A supermarket needs to produce carrier bags. It can use either polythene or biodegradable plastic.
Measurement | Maximum Weight (N) | |
Polythene | Biodegradable Plastic | |
1 | 25.45 | 19.80 |
2 | 25.50 | 19.75 |
3 | 25.40 | 19.80 |
4 | 52.50 | 19.85 |
5 | 25.50 | 19.90 |
- When analysing data like this, look to see if there are any OUTLIERS, this could have been caused by human error.
- The TRUE VALUE can be found from the range.
- Calculating the mean
When it comes to I/GCSE Chemistry, overall the data shows that polythene can support more weight than the biodegradable plastic before breaking. In terms of strength, this makes polythene the most suitable material from which to make carrier bags.
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