Density And Matter Third Year Revision

Question 1

What is density

Answer 1

Density tells us how tightly packed the particles are in something.
• Density is the mass per unit volume of an object.
• We can write this as: Density = mass (g)
Volume (cm3)

Question 2

How do we find the density of regular shapes

Answer 2

To find out the density of regular shapes , we must first measure the mass and the volume.
• We measure the mass on a scales in gramms
• We measure the volume using a ruler to measure the length, width and height and multiply all three numbers.

Question 3

How do we measure the density of irregular solids

Answer 3

• Volume is measured using a graduated cylinder by water displacement.
• Density is calculated in the same way

Question 4

How do we measure the density of liquid

Answer 4

• Volume read from volumetric flask.
• Density calculated in the same way.

Question 5

How do we predict if something will float or not

Answer 5

• Objects which have a higher density will sink in water whereas objects with a lower density will float.

Question 6

Elements

Answer 6

Materials that are made of only one type of atom.

Question 7

Molecules

Answer 7

atoms that exist in pairs or groups.

Question 8

How many elements are there?

Answer 8

There are over 100 different times of elements.

Question 9

atoms

Answer 9

What all matter is made out of