Table of contents

1. Matter and Measurements4h 31m
2. Atoms and the Periodic Table5h 23m
3. Ionic Compounds2h 18m
4. Molecular Compounds2h 18m
5. Classification & Balancing of Chemical Reactions3h 17m
6. Chemical Reactions & Quantities2h 27m
7. Energy, Rate and Equilibrium3h 46m
8. Gases, Liquids and Solids3h 25m
9. Solutions4h 10m
10. Acids and Bases3h 29m
11. Nuclear Chemistry56m
BONUS: Lab Techniques and Procedures1h 38m
BONUS: Mathematical Operations and Functions47m
12. Introduction to Organic Chemistry1h 34m
13. Alkenes, Alkynes, and Aromatic Compounds2h 12m
14. Compounds with Oxygen or Sulfur1h 6m
15. Aldehydes and Ketones1h 1m
16. Carboxylic Acids and Their Derivatives1h 11m
17. Amines39m
18. Amino Acids and Proteins1h 51m
19. Enzymes1h 37m
20. Carbohydrates1h 41m
21. The Generation of Biochemical Energy2h 8m
22. Carbohydrate Metabolism2h 22m
23. Lipids2h 26m
24. Lipid Metabolism1h 45m
25. Protein and Amino Acid Metabolism1h 37m
26. Nucleic Acids and Protein Synthesis2h 54m

1. Matter and Measurements

Physical & Chemical Changes

GOB Chemistry

1. Matter and Measurements

Physical & Chemical Changes

Previous problemNext problem

2:26 minutes

Problem 12c

Textbook Question

What type of change, physical or chemical, takes place in each of the following?
c. A tree is cut into boards at a saw mill.

Verified step by step guidance

Identify the key characteristics of physical and chemical changes. A physical change involves a change in the state, shape, or size of a substance without altering its chemical composition. A chemical change results in the formation of new substances with different chemical properties.

Analyze the process described in the problem. Cutting a tree into boards involves changing the shape and size of the material, but the chemical composition of the wood remains the same.

Determine whether any new substances are formed during the process. Since no new substances are created and the wood remains chemically identical, this indicates a physical change.

Consider examples of similar processes, such as breaking a piece of glass or shredding paper, which are also physical changes because the material's chemical structure is unchanged.

Conclude that cutting a tree into boards at a sawmill is a physical change because it only alters the physical form of the wood without changing its chemical composition.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Play a video:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Physical Change

A physical change involves a transformation that does not alter the chemical composition of a substance. In this type of change, the material may change its form, size, or state, but its molecular structure remains intact. For example, cutting a tree into boards alters its shape and size but does not change the wood's chemical properties.

Chemical Change

A chemical change results in the formation of one or more new substances with different chemical properties. This type of change involves breaking and forming chemical bonds, leading to a change in the molecular structure. Examples include combustion or rusting, where the original substances are transformed into entirely new materials.

Wood as a Material

Wood is an organic material derived from trees, primarily composed of cellulose, hemicellulose, and lignin. Understanding wood's properties is essential when discussing changes it undergoes. When a tree is cut into boards, it retains its chemical structure, indicating a physical change, while any subsequent processes like drying or treating the wood may involve chemical changes.

Watch next

Master Physical and Chemical Changes with a bite sized video explanation from Jules

Start learning