Physical and Chemical Changes – Grade 7 Science Worksheets
7th Grade Free Worksheets
- Elements & Compounds-1
- Elements & Compounds-2
- Solar Energy-1
- Solar Energy-2
- Photosynthesis-1
- Photosynthesis-2
- Photosynthesis-3
- Digestive System-1
- Digestive System-2
- Electricity and Magnetism
- Law of conservation of energy
- Law of Conservation of Mass
- Periodic table
- Properties of Matter
- Waves
- Energy Resources
- Weather and Climate
- Immune , Circulatory and Digestive Systems
- Organs in Multi-cellular Organisms
- Sedimentary, Igneous, and Metamorphic Rocks
- Structure of the Earth
- Physical and Chemical Changes
- Scientific Method
- Cycles in Nature
- Environmental Science
- Renewable and Non-renewable energy Resources
- Characteristics of Living Organisms
- Life Science
- Earth and Space Science
- Solar Eclipse
- Heat Technology
- Newton’s Laws of Motions
- Physical Science
- Tools, Measurement and SI Units
- Earth Atmosphere
- Interactions of Living things
- The Earth Ecosystem
- Organelles in Plant and Animal cells
- Layers of the Earth
Every substance has a certain property like –
Physical Properties: A physical property of a substance means its shape, size and physical state of a substance. For example: when water boils it turns to vapor but its still water in gaseous form. Although its state changes.
Every substance has a certain property like –
Physical Properties: A physical property of a substance means its shape, size and physical state of a substance. For example: when water boils it turns to vapor but its still water in gaseous form. Although its state changes.
Chemical Properties:The basic inherent nature of a substance is known as chemical properties. For example mold on a piece of bread. Once yeast is formed, we would never get the original bread form.
All such changes can be separated into two types – Physical and Chemical.
What are the physical changes?
- Physical changes are the changes in physical properties which does not involve new produce of substances. Changes are very much reversible like – melting of ice.
Nature of a Physical change –
- Physical changes are mostly reversible
- Physical properties of a substance only changes not its chemical properties
- New substance is not created in this process
Chemical changes are permanent changes which happen to the original substances making it lose its inherent properties. Changes like these are irreversible like – rusting of iron, burning of wood.
Credit: https://pixabay.com/en/chain-rust-iron-metal-macro-rusty-566778/
Nature of a Chemical change-
- A chemical change cannot be brought to original by physical methods. Chemical properties of substance change
- In a chemical change, new substances are formed
- Chemical changes are not reversible
- The chemical composition and properties of a substance changes during a chemical chnage
- Gas evolves
Results of Chemical Change:
- Change in smell.
- Gas evolves.
- Heat is produced.
- Sound is produced.
- Change in color.
What is an example of a physical change?
Heating of water: When water is heated no new substance is formed. No change in color or smell.
Paper folding: A paper can be folded or refolded and unfolded again hence it is an example of physical change. Here, no new substance is formed in this. So, it is a physical change.
Molding of clay: Clay when molded. Shape changes, its size changes but no gas evolves, or no new substance is formed and no smell is produced.
Cutting of wood: When we cut a piece of wood we get more number of wood pieces but there is no new substance produced, no gas evolution and no change in the property of wood.
Crushing paper: Here, again no new substance is formed. Can be brought back to its original form. No gas is released.
Mixing salt in water: Water and salt can be easily separated. This is a physical change because no new substance is formed and the chemical properties of substances involved are completely intact.
Chemical Changes
When properties of substance change and new substances are formed is called chemical changes. Sometimes chemical changes are irreversible. In chemical change where it can be reversed chemical properties of substance alter and a new substance is formed.
What is an example of a chemical change?
Burning of anything like paper, wood, fuel etc. When a substance burns, many new substances are formed like ash and carbon dioxide is formed. A burnt substance cannot be turned to the original form by any chance since ash is what remains.
Hence, burning of a substance is an irreversible chemical change.
Wax melting: This is a reversible change because wax solidifies in room temperature. There is no new substance formed. No gas emissions and chemical property of wax does not change. | ![]() |
Cooking vegetables: This involves baking or frying of food which then cannot be brought back to the original self. Smell is produced. It’s a new substance altogether. Digestion is an example of chemical change. New substances are produced. Food is broken down. Energy is released, cannot be converted to food again. | ![]() |
Weathering of rocks: Rock formation involves immense heat and pressure. Running water on them, intense wind and expansion as a result of heat. These changes are irreversible. | ![]() |
I. State True or False –
- Melting of wax is a chemical change.
- A physical change involves formation of new products.
- A chemical change is irreversible.
- Burning of paper is a chemical change.
- Chemical change cannot be reversed by simple physical means.
Answer Key
- False
- False
- True
- True
- True
eTutorWorld offers affordable one-on-one live tutoring over the web for Grades 3-12, Test Prep help for Standardized tests like SCAT, SSAT, SHSAT, ISEE, AP and community college courses. You may schedule online tutoring lessons at your personal scheduled times, all with a Money-Back Guarantee. The first one-on-one online tutoring lesson is always FREE, no purchase obligation, no credit card required.
For answers/solutions to any question or to learn concepts, take a FREE Demo Session.
Our Learning by Design methodology focuses exclusively on the individual student. Our tutors are specially trained to identify and diagnose the needs and interests of each student and plan lessons accordingly.
7th Grade Free Worksheets
- Elements & Compounds-1
- Elements & Compounds-2
- Solar Energy-1
- Solar Energy-2
- Photosynthesis-1
- Photosynthesis-2
- Photosynthesis-3
- Digestive System-1
- Digestive System-2
- Electricity and Magnetism
- Law of conservation of energy
- Law of Conservation of Mass
- Periodic table
- Properties of Matter
- Waves
- Energy Resources
- Weather and Climate
- Immune , Circulatory and Digestive Systems
- Organs in Multi-cellular Organisms
- Sedimentary, Igneous, and Metamorphic Rocks
- Structure of the Earth
- Physical and Chemical Changes
- Scientific Method
- Cycles in Nature
- Environmental Science
- Renewable and Non-renewable energy Resources
- Characteristics of Living Organisms
- Life Science
- Earth and Space Science
- Solar Eclipse
- Heat Technology
- Newton’s Laws of Motions
- Physical Science
- Tools, Measurement and SI Units
- Earth Atmosphere
- Interactions of Living things
- The Earth Ecosystem
- Organelles in Plant and Animal cells
- Layers of the Earth
+1-269-763-4602
+1-269-763-5024
Quick Links
Follow Us
Give Your Child The eTutorWorld Advantage
Research has proven that personal online tutoring not just cements school learning, it helps build student confidence. eTutorWorld provides the best K-12 Online Tutoring Services so you can learn from the comfort and safety of your home at an affordable cost.
Be it an exam, class test or a quiz, eTutorWorld’s Math, Science and English tutors are responsible for your academic progress. Meet your personal coach at your convenient day and time to get help for Grade 3-12 Math, Science and English subjects and AP, SAT, SSAT and SCAT Test Prep help and test practice. All our tutors are graduates and bring with them years of teaching experience to the tutoring lessons.
Our ‘Learning by Design’ methodology makes sure that each student is at the center of the teaching-learning process. All tutoring sessions start with a question to the student ‘What do you want to learn today?’ Hence, tutors diagnose your skills and recognize your requirements before the actual tutoring happens. Post every tutoring session, an individualized worksheet is emailed to the student to assimilate learned concepts. Regular formative assessments are used to evaluate a student’s understanding of the subject.
The state of the art technology used is stable, user friendly and safe. All you need is a computer or a tablet and an internet connection. The easy-to-use web conferencing software requires a one time download, using which the student can talk and chat to the tutor, annotate on an interactive shared whiteboard or even share documents, assignments or worksheets.
All tutoring sessions are recorded and made available for a month so you can review concepts taught.
Email or call our support team with any issues or questions – we are here for you 24X7.
Also, download free printable math and science worksheets in pdf format and solve SCAT and SSAT Practice Tests online. Sign up for a Free Trial Lesson Today!
Thousands have taken the eTutorWorld Advantage – what are you waiting for?
© 2019 eTutorWorld - Online Tutoring and Test Prep | All rights reserved