Starter

• Label your book like so:

• At the BACK of your book• Draw a picture to show these words:

• Atom• Ionic Bonding• Metal• Limestone

Name: Form:

10YSc2 Science

Mrs Bradford 1.16

Starter: FeedbackAtom Ionic Bonding

Metal Limestone

Starter

• Put the liquids in order of how thick they are:

C1.4.1 - Alkanes

Objective: to recall the main principles of chemistry covered so far and

describe the structure of the hydrocarbon family of alkanes

Outcomes:

• Good: You can define the term mixture and apply it to crude oil

• Better: you can draw the structure of the first four alkanes

• Even Better If: you can create a model of the first four alkanes

What is a Mixture?

• Salty water• The air in the room• A cake• Fruit salad• Your blood• Glucose• Ice cubes in water

Extension - How can you tell they are a mixture?

Task: Which of these are mixtures?

What is an Alkane?

• An alkane is a type of HYDROCARBON

• It is made up of only 2 elements – HYDROGEN and CARBON

• They form CHAINS with the carbons long the centre and hydrogens bonded to the carbons

• As they get longer, they get HEAVIER

Outcomes:

• Good: You can define the term mixture and apply it to crude oil

• Better: you can draw the structure of the first four alkanes

• Even Better If: you can create a model of the first four alkanes

MethaneOne carbon atom bonded to four hydrogen

atoms. Each line represents a single covalent bond.

Ethane

Two carbon atoms six hydrogen atoms

Propane

Three carbon atoms eight hydrogen atoms

Butane

Four carbon atoms ten hydrogen atoms

Outcomes:

• Good: You can define the term mixture and apply it to crude oil

• Better: you can draw the structure of the first four alkanes

• Even Better If: you can create a model of the first four alkanes

Task

• In pairs• You have to create a model of the

first four alkanes from the objects in your pack

• They have been counted out exactly – so NO munching just yet!

• When you have finished, hands up to let me know

Next Task

• You are going to time how long it takes to eat each model

• Present your results in a results table:

Alkane Time taken to eat (s)

Methane

Ethane

Propane

Butane

Can you spot a pattern?

Every time we increase the number of carbons what happens to the number of hydrogens?

We can work out a general formula for any alkane it is:

CnH2n+2 where n is the number of carbon atomsand 2n+2 is the number of hydrogen atoms

Counting in chemistry

• Rather than the numbers 1,2,3 and 4 when we are counting in chemistry we use the terms:

• meth_ = 1• eth_ = 2• prop_ = 3• but_ = 4• The first four alkanes are therefore

called methane, ethane, propane and butane.

Outcomes:

• Good: You can define the term mixture and apply it to crude oil

• Better: you can draw the structure of the first four alkanes

• Even Better If: you can create a model of the first four alkanes and identify a pattern in the number of hydrogen and carbon atoms

Test your knowledge - Quiz

1. What is the name of the alkane with the formula CH4?

2. What is the name of this alkane?

3. Draw a molecule of propane showing all the bonds.

Test your knowledge - Quiz

1. What is the name of the alkane with the formula CH4 - methane

2. What is the name of this alkane? ethane

3. Draw a molecule of propane showing all the bonds.