Kinetic Energy & Classification of Matter

20 Q&A flashcards covering kinetic energy, states of matter, pure substances, elements, compounds, and types of mixtures.

What is kinetic energy?

The energy an object possesses due to its motion.

How does speed affect kinetic energy?

The faster an object moves, the greater its kinetic energy.

Give three everyday examples of kinetic energy.

Throwing a ball, riding a bicycle, and a moving car (also a bouncing basketball).

What are the three primary states of matter?

Solid, liquid, and gas.

At the broadest level, how is all matter classified?

Into pure substances and mixtures.

What is a pure substance?

A material made of only one kind of particle (atoms or molecules) with constant composition; cannot be separated by physical means.

Define element.

A pure substance consisting of only one kind of atom.

Define compound.

A pure substance composed of two or more different atoms chemically bonded in a fixed proportion.

Can elements be separated into simpler substances?

No, elements cannot be broken down into simpler substances.

How can compounds be separated?

They can be broken down into simpler substances by breaking the chemical bonds between atoms (chemical change).

What is a mixture?

A combination of two or more substances that are not chemically combined and can be physically separated.

Define homogeneous mixture.

A mixture with a uniform composition and identical properties throughout (e.g., vinegar).

Define heterogeneous mixture.

A mixture whose components have different properties in different parts of the sample (non-uniform).

Can mixtures be separated by physical means?

Yes, because the substances in a mixture retain their individual properties.

Name the three particle-based categories of mixtures mentioned.

Solutions, colloids, and suspensions.

What is a solution?

A homogeneous mixture of two or more substances with particles at the molecular or ionic level.

What is a colloid?

A mixture in which particles are evenly dispersed throughout another substance but are larger than in a solution and do not settle out.

What is a suspension?

A mixture where larger particles or droplets are dispersed in a liquid or gas and will eventually settle out if left undisturbed.

Which category of matter has constant composition: pure substances or mixtures?

Pure substances.

Which category of matter has variable composition: pure substances or mixtures?

Mixtures.