Year 10 Science · Unit 2 · Lesson 16

Chemical Reactions and the Environment

Foundation Worksheet

Name

Date

Class

Learning Goals

Sort materials and fuels by their biodegradability and carbon impact.
Explain why burning fossil fuels increases atmospheric CO₂ faster than natural cycles can absorb it.
Describe the environmental advantages of alternative fuels such as ethanol and hydrogen.

Warm Up

Sort it!

Write each item from the pool into the correct category box below. Each item belongs to exactly one category.

Apple core Plastic shopping bag Ethanol from sugarcane Coal Cardboard box Polystyrene foam cup Hydrogen gas (from solar) Petrol (gasoline) PLA bioplastic bag Natural gas (methane)

Biodegradable

Non-biodegradable

Low-carbon fuel

High-carbon fuel

Your Turn

Fill the gap

Choose the correct word from the word bank to complete each sentence. Two words will NOT be used.

photosynthesis carbon dioxide ocean carbonic acid pH combustion biodegradable microplastics hydrogen nitrogen

When fossil fuels burn, is released into the atmosphere faster than can absorb it. About 30% of this gas dissolves in the , forming . This lowers the of seawater, threatening shell-forming organisms. Plastics are non- polymers that break into tiny fragments called that enter food chains. When fuel burns, it produces only water vapour, zero CO₂ emissions at the point of use.

Show What You Know

1. Explain why burning sugarcane ethanol is considered lower in net carbon emissions than burning the same amount of petrol.

Recall 2 marks

2. Indigenous Australians have practised controlled burning for thousands of years. Give one chemical reaction that occurs during a controlled burn and explain one environmental benefit of this practice.

Recall 2 marks

Wrap Up

In one sentence, explain how a single chemical reaction (combustion) connects to climate change, ocean acidification, and coral bleaching.