Page 12 - Science Course 3 (Book 2)

Mo8-L1b: How Do the Changes of Matter Affect Mass?

The only sure sign of a chemical change is the How Do the Changes of Matter
formation of a new substance. Mo8–L1b
Affect Mass?
KEY CONCEPTS:
1. How do physical and chemical changes affect
mass?

Vocabulary A-Z

Let us learn some vocabulary

Law of Conversation Mass
law that states that the total mass of the reactants
before a chemical reaction is the same as the total
mass of the products after the chemical reaction.

Key Concept

What are Physical and Chemical Changes?

How are chemical changes different from physical
changes?

Let’s Begin

What are Chemical Changes?

For many reactions, changes in physical properties,
such as color or state of matter, are signs that a
chemical change has occurred.

All chemical reactions involve energy changes.
Thermal or light energy is often needed for a
chemical reaction to take place.

SUMMARY

What are Physical and Chemical Changes?

The identity of a substance does not change
during a physical change such as a change in
the state of matter.

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