Molecules in Density
Molecules are very tightly packed together in a substance. Is the substance more dense OR less dense?
The substance is more dense because the molecules are very tightly packed.
Is a piece of wood floating on water more dense OR less dense than water?
The piece of wood is less dense than water because it is floating on water.
What is mass?
Mass is the amount of matter in a substance.
Mass is measured in grams (g) with a balance.
Molecules in a substance are loosely packed together with lots of space between molecules. Is the substance more dense OR less dense?
The substance is less dense because the molecules are loosely packed and have a lot of space between them.
Is a rock at the bottom of a pool more dense than water OR less dense than water?
The rock is more dense than water because it is sinking in the water.
What is volume?
Volume is the amount of space a substance takes up.
Volume is measured in liters (l) with a graduated cylinder.
Meters cubed (m3) with a ruler = Length x Width x Height.
As a substance heats up, the molecules move further apart, is the substance becoming more dense OR less dense?
The substance is becoming less dense because the molecules are moving further apart and are less packet together.
Oil always floats on top of water, they never mix together. Why don't oil and water ever mix?
Oil and water never mix because they have different densities. Oil floats and is less dense than water.
What is the mathematical formula for density?
Density is mass divided by volume.
D = m/v
D = mass/volume
As a substance cools down, the molecules move closer together, is the substance becoming more dense OR less dense?
The substance is more dense because the molecules are moving closer together and becoming more packed.
Why does an egg sink in water?
Because the egg is more dense than the water.
You have a volume of 1ml and a mass of 1g of water. What is the density of water?
The density of water is:
1g / 1ml = 1 g/ml
Which is more dense, a basket ball OR a bowling ball?
A bowling ball is more dense because it is packed with more matter.
A whole paperclip sinks in water. Will the paper clip sink if it is broken in half?
Yes, the paperclip will still sink. Density is a physical property of matter. The density of a substance does NOT change.
What is the density of a substance That has a mass of 10g and a volume of 5cm3?
The density of the substance is:
10g / 5cm3 = 2g/cm3