Chem Review 1

Which is the best example

of a pure substance?

• peanuts

• milk

• gold

• air

Which shows one example of a physical change and one example of a chemical change?

• boiling water and melting wax

• rusting iron and baking a cake

• dissolving powder and shredding paper

• freezing water and burning coal

How can mixtures best be described?

• made of one element

• made of different elements that are all chemically bonded together

• made of different elements that are not all chemically bonded together

In which state of matter will the atoms of an element be tightly packed together?

• gas

• liquid

• solid

Which is a mixture?

• water

• salad

• table salt

Based on how the atoms are packed together in arrangements, which is an element?

• glass

• carbon

• silver nitrate

What chemical reaction results in

the formation of a solid?

• acid base reaction

• endothermic

• precipitate

When baking soda and vinegar react, the product includes bubbles. What has most likely occurred?

• gas formation

• exothermic reaction

• precipitate formation

What is the best evidence that a gas has been produced in a chemical reaction?

• change in color

• formation of bubbles

• change in temperature

What is the best evidence for a chemical reaction?

• color change

• cutting metal

• change of state