Exploring the Concept of Density: Why Oil Floats on Water

What is density a measure of?

• The mass of an object per unit volume

• The volume of an object per unit mass

• The volume of an object per unit weight

• The weight of an object per unit volume

Why does a log of wood float on water?

• Because it is hollow

• Because it is lighter than water

• Because it has less density than water

• Because it is made of wood

Why does a piece of rock sink in water?

• Because it is heavier than water

• Because it is not buoyant

• Because it has more density than water

• Because it is solid

Why does a helium-filled balloon rise in the air?

• Because helium has less density than air

• Because helium is a gas

• Because helium is buoyant

• Because helium is lighter than air

What is one reason oil floats on water?

• Because oil is a liquid

• Because oil is immiscible with water

• Because oil has less density than water

• Because oil is lighter than water

What does it mean when two liquids are immiscible?

• They mix together easily

• They have the same density

• They do not mix together

• They are both gases

What happens when oil and water are shaken together and then left undisturbed?

• They separate into two layers

• They evaporate

• They mix completely

• They form a single layer