1st Semester Exam Flashcards

Front

What best describes a pure substance?

Back

A material with a uniform and definite composition

Front

What happens to the particles in a solid when thermal energy is added?

Back

They move faster and spread apart

Front

Which property is a chemical property of matter?

• Melting point
• Density
• Reactivity
• Boiling point

Back

Reactivity

Front

Which of the following is an example of a physical change? Rusting of iron, Burning of wood, Melting of ice, Baking a cake

Back

Melting of ice

Front

What does the atomic number of an element represent?

Back

The number of protons in an atom

Front

How can a compound be distinguished from a mixture?

Back

A compound has a fixed composition

Front

What occurs to the particles in a gas when thermal energy is removed?

Back

They move slower and come closer together

Front

Which of the following is a physical property of matter? Combustibility, Reactivity, Density, Flammability

Back

Density

Front

Which of the following changes is a chemical change? Dissolving sugar in water, Freezing water into ice, Burning a candle, Melting butter

Back

Burning a candle

Front

What is the role of neutrons in an atom?

Back

They contribute to the mass of an atom