Physical and Chemical Properties/Changes

Which one of these is not an example a physical property?

• Malleability

• Luster

• Shape

• Combustibility

• Boiling point

Answer explanation

A physical property is a characteristic that is observed or measured without changing the identity of the substance/object.

Which of the following is not an example of Physical Change?

• Squeezing an orange for juice

• Cracking open an egg

• Burning of Paper

• Cutting hair

• Crushing ice

Answer explanation

A physical change occurs when a substance/object is changed. The substance/object does not change its composition. The change is in its appearance only.

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NGSS.MS-PS1-4

Chemical Property: Select each answer that represents a chemical property & has the ability to change the identity of a subject or an object.

• Tarnish

• Spoil/Rot

• Rust

• Flammability

• Ability to react with water

Answer explanation

A chemical property is a characteristic or ability of a substance/object that can only be observed by changing the identity of the substance/object.

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Chemical Change: Which of the following are true statements?

• Chemical changes cannot be reversed.

• The change produces a new substance with different properties.

• A log burning: as it burns it gives off heat, light, and gas.

Answer explanation

Once the

burning is complete, the new substance is ash.

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Chemical Change indicators: What is an examples?

Answer explanation

Fire on anything will produce a chemical change

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Chemical Change Examples:

• Baking bread/cake

• Frying an egg

• Milk souring

• Breaking Glass

• Gas burning

Answer explanation

Overall, the most important thing to remember is that a chemical reaction produces a whole new chemical compound. J

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To identify the type of change:

Ask yourself: Was a NEW substance/object created?

If NO - A physical change occurred

If YES - A chemical change occurred

Answer explanation

Law of Conservation of Mass: During physical and chemical changes, mass cannot be created nor destroyed, it just changes form.

When wood burns, the mass of the soot, ashes, and gases/smoke equal the original mass of the charcoal (blackened wood) and oxygen when it first reacted.

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