Curriculum

Course: Science — Second Preparatory

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Curriculum

Science — Second Preparatory

Unit 1: Matter and Energy

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Unit 2: Matter and Chemical Reactions

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Unit 3: Energy Flow in Photosynthesis and Respiration

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Unit 4: Geological Processes

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Text lesson

Changes to Earth’s Surface

Science — Second Preparatory

Changes to Earth’s Surface

Applications and examples

Applications and examples

Comparison aspect	Main idea	Keywords
Experiment 1: weathering by freezing.	Fill a sealed glass bottle with water and place it in a freezer. Water expands by about 9% when it freezes and the bottle may crack. This is similar to what happens to rocks when water freezes in their cracks	Fillsealedglassbottle
Experiment 2: erosion by water.	Spread sand on a tilted tray and pour water over the top. The water carries some sand down the tray and the sand settles at the less steep end. This is a simple model of erosion and deposition	Spreadsandtiltedtray
Experiment 3: chemical weathering.	Place a piece of limestone in dilute hydrochloric acid. Bubbles of carbon dioxide gas appear and the piece gradually wears away. This shows how acidic water dissolves limestone in nature	Placepiecelimestonedilute

Example from Egypt→the sand dunes of the Western Desert were formed by wind that carried sand from one place to another.

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