PAP Matter and Atoms

Front

What is a pure substance?

Back

A pure substance is a material that has a constant composition and consistent properties throughout. It can be an element or a compound.

Front

Which of the following is NOT a pure substance: water, brass, or oxygen?

Back

Brass is not a pure substance; it is an alloy composed of multiple elements.

Front

What property can only be determined through a chemical change?

Back

Flammability is a property that can only be determined through a chemical change.

Front

What are the components of the ion represented by 24Na+1?

Back

The ion 24Na+1 has 11 protons, 13 neutrons, and 10 electrons.

Front

How is sodium carbonate (Na2CO3) classified?

Back

Sodium carbonate (Na2CO3) is classified as a compound.

Front

What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition.

Front

Give an example of a physical change in metals.

Back

Examples of physical changes in metals include melting, bending, and polishing.

Front

What is rusting, and how is it classified?

Back

Rusting is a chemical change that occurs when iron reacts with oxygen and moisture, forming iron oxide.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance that cannot be broken down into simpler substances, while a compound is a substance formed when two or more elements chemically bond together.

Front

What is the significance of the atomic number?

Back

The atomic number represents the number of protons in an atom and determines the element's identity.