Understanding Mixtures and Substances

Which of the following is a pure substance?

• Saltwater

• Oxygen gas

• Sand and iron filings

• Lemonade

Tags

NGSS.MS-PS1-4

What is the smallest unit of an element that retains the properties of that element?

• Molecule

• Atom

• Compound

• Mixture

Which of the following elements is likely to have similar properties to chlorine?

• Sodium

• Argon

• Fluorine

• Carbon

Which property is independent of the amount of the sample?

• Mass

• Volume

• Density

• Weight

Which of the following is a chemical change?

• Melting ice

• Dissolving sugar in water

• Burning wood

• Boiling water

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

How can you distinguish a mixture from a pure substance?

• A mixture has a fixed composition.

• A pure substance can be separated by physical means.

• A mixture can be separated into its components by physical means.

• A pure substance is always a liquid.

Which sub-atomic particle has a negative charge?

• Proton

• Neutron

• Electron

• Nucleus

Why are elements in the same group of the periodic table similar?

• They have the same number of protons.

• They have similar atomic masses.

• They have the same number of valence electrons.

• They have the same number of neutrons.

Which of the following is a physical property?

• Reactivity with acid

• Flammability

• Melting point

• Ability to rust

Which of the following processes is a physical change?

• Rusting of iron

• Baking a cake

• Freezing water

• Burning gasoline

Tags

NGSS.MS-PS1-4