Starter Activity: Logical Thinking

Use the 12 evidence cards that you have been given to help you solve this problem.

A

B

C

D

E

F

G

H

The measuring cylinder on the right has eight different liquids in it. You have a copy of this measuring cylinder in your exercise book. Your task is to use the twelve evidence cards to decide on the name of each of the eight liquids.

To help you complete this activity:

Lighter liquids will float on top of heavier ones.

The cards on your table show what happens when two of these liquids are placed in the same beaker. In each case, one will float and one will sink. Looking at all of

the evidence on the cards, combine this together to logically deduce which liquid is which.

Aniline WaterCrude

OilMilk Olive Oil

CoconutOil

Petrol (gasoline)Sea Water

Starter Activity: Logical Thinking

Use the 12 evidence cards that you have been given to help you solve this problem.

A

B

C

D

E

F

G

H Petrol

Olive Oil

Crude Oil

Coconut Oil

Pure Water

Aniline

Sea Water

Milk

What can you tell me about these four diagrams?

WALT: We Are Learning To

In the lesson today, we will learn…•What density is and how it is related to floating and sinking.

Keywords

WILF: What Im Looking For

By the end of the lesson, I would like you to be able to…• Measure the density of a regular shaped object.• Remember the calculation needed to work out density.• Use ideas from the particles topic to explain density.• Use a materials density to decide if an object will float or sink.

Density

Particles

Volume

Mass

Archimedes

Working out the Density of different materials

To work out the density of any particular material, you need two different pieces of information. These are:

How much stuff there is in the material (measured in g)

How much space the material takes up (measured in cm3)

To work out the density of a material, you do the following calculation:

Working out the Density of different materials

Measured in g Measured in cm3 Measured in g/cm3

Measured using scales

Measured using a ruler

Find out the width, the

length and the height

Multiply these together

Working out the Density of different materials

1cm x 1cm x 1cm = 1cm3

1cm x 5cm x 1cm = 5cm3

1cm x 4cm x 2cm = 8cm3

2cm x 3cm x 2cm = 12cm3

Working out the Density of different materials

10cm x 5cm x 7cm = 350cm3

7cm

10cm 5cm

Working out Density

You will be given a set of different materials. For each one, you will need to work out the density. Record your results in a table like the one below:

Material Mass (g) Volume (cm3) Density (g/cm3)

Plastic

Stone

Lead

Aluminium

Brass

Copper

Polystyrene

Use these results to rank the materials in order of most dense to least dense.

I want to find out the density of this rock…..

Working out the volume of an irregular object

Stage 1 Stage 2 Stage 3

Floating or Sinking?

Density of Water is 1g/cm3

Density of Bone is 1.8g/cm3

Density of Cork is

0.24g/cm3

Density of Cork is

3.01g/cm3

Density of Ice is

0.90g/cm3

Density of Ice is

0.77g/cm3