Btec – Chemistry 1Btec – Chemistry 1Lesson 1 – Group 1 MetalsLesson 1 – Group 1 Metals

Patterns in the periodic table

Starter ActivityStarter Activity

• Use the white boards...• In ONE minute name as many

chemicals as you can

What are we going to learn?What are we going to learn?

Essential...• What the periodic table is• That the position of an element in the periodic table

can provide information about its electronic structureMerit grade...• That elements in groups have similar reactions• Be able to predict the reactions of elements in the

periodic tableExtension / Distinction...• Reactions of elements can depend on their electronic

structure

The periodic tableThe periodic table

Task 1 (10 mins)...Task 1 (10 mins)...

In groups look at the periodic table, 1. Why is water not in the periodic table?2. Look at the elements either side of the

black zig-zag line – what do you think this line seperates?

3. Is there any pattern in the numbers that are written by each element?

One person from each table can use http://www.webelements.com/to help...

Demonstration...Demonstration...(Na, Li, K)(Na, Li, K)

Element Appearance

Reaction with water

Marks out of 10

Na

Li

K

Rb

Cs

Fr

20 mins

We have looked We have looked at Li, Na and Kat Li, Na and K

Now make Now make predictions for predictions for Rb, Cs and Fr Rb, Cs and Fr

Watch DVD and Watch DVD and complete table...complete table...

Patterns in the periodic tablePatterns in the periodic table

Reactivity• Group 1 elements become more

reactive as you go down the group• Make an annotation on your

worksheet

Watch introduction to periodic Watch introduction to periodic table and answer questions...table and answer questions...

Plenary...Plenary...• In groups – on your white board...1. What is the periodic table?2. Draw an outline of the Periodic table,

indicate a group and a period3. What can you say about the reactions

of elements in a group?4. Were there any mistakes in the DVD?

Extension...Extension...

• Use www.webelements.com to find out about the reactions of group 7 elements.

• What sort of reactions take place?• Are they similar or different?

Not in this lesson...Not in this lesson...

Patterns in the periodic tablePatterns in the periodic table

• It is a bit like gravity• The nucleus of an atom ‘pulls’ and

‘holds’ the electrons in orbit around the nucleus

Patterns in the periodic tablePatterns in the periodic table

• The bigger the atom gets, the easier it loses an electron

Li K

Pattern in the periodic tablePattern in the periodic table

• So potassium is more reactive than lithium• Francium is the most reactive as it is the

largest atom

• The nucleus is further away, so the pull is less

Li K

Pattern in the periodic tablePattern in the periodic table

• Group 7 elements become less reactive as they go down the group

• Why?

Pattern in the periodic tablePattern in the periodic table

• Again it is a bit like gravity• The smaller the atom the easier it gains an electron

F Cl

Pattern in the periodic tablePattern in the periodic table

• So Chlorine is less reactive than Fluorine• Astatine is the least reactive in the group as it has the largest atom and the

smallest ‘pull’

F Cl

Pattern in the periodic tablePattern in the periodic table

• Group 8 has a full outer shell• It does not want to lose or gain electrons • So they are very un-reactive

Ne Ar

Boiling pointsBoiling points

• The boiling points of group 1 decrease down the group

• The boiling points of group 7 increase down the group

QuestionsQuestions

1. What happens to the boiling point of the metals as you move down group 1

2. Group 1 atoms want to loose an electron, do you think it would be easier to remove an electron from Lithium or Cs?

3. What is the most reactive element in group 1?4. Group 7 atoms want to gain an electron, which atom would most

strongly attract an electron to the ‘gap’ in the outer shell?5. Which is the most reactive element in group 7?6. Group 8 elements are unreactive, with reference to their electron

structure, why is this?

Structure of the

Nucleus

What have we learnt?What have we learnt?

We have learnt……• That the location of an element in

the periodic table can provide information about its electronic structure

• That elements in groups have similar reactions

• Reactions of elements can depend on their electronic structure

Structure of the Nucleus…Structure of the Nucleus…

What the numbers mean…What the numbers mean…

• Big number – Atomic MassTotal number of bits in the nucleus

• Small number – Atomic NumberNumber of protons in the nucleus

What is the atomic mass?What is the atomic mass?What is the atomic number?What is the atomic number?

• Look at your periodic tables…

• What atom is this…(the red ones are protons)

Element Atomic number

Mass number

Number of

protons

Number of

neutrons

Number of

electrons

H 1 1 1 0 1

He 2 4 2 2 2

Li 3 7

C 6 6

N 14 7

O 8 8

Na 23 11

Mg 12 12

Cl 17 35

Cl 17 37

Cu 29 63

Cu 29 65

Isotopes

Name Protons Neutronselectrons

80Br

35

40

18

35

17

37

17

• Isotopes are identical in their chemical reactions.

• This is because they have the same number of protons and the same number of electrons.

• The uncharged neutrons make no difference to chemical properties but do affect physical properties such as melting point and density.

Isotopes…Isotopes…

Today's wonderful activities…Today's wonderful activities…

• Complete worksheet (Atomic Structure)

• Applied science workbookQuestions (p.g. 14-15)

• Complete worksheet

Assignment

Assignment…Assignment…Scenario…. Produce a magazine article for a forensic science magazine. Make a title page with …• A title (e.g. ‘All about atoms’)• A logo used on the title page and also every other page • ‘South West edition’ or similar to show that it’s a local

periodical• Date• Price

For the article itself …• text boxes can create columns of text just like a real article in

a newspaper or magazine. • Pictures can be hand drawn onto printed sheets or students

can cut & stick what they already have• Every page, including the title page must be numbered

Grading criteria P1 • Describe atomic and electronic structures of elements 1-20, including isotopes, in the periodic table

Grading criteria M1 • Describe the patterns and trends of chemical properties of groups 1 and 7 in the periodic table

Grading criteria D1 • Explain the patterns and trends within groups 1 and 7 in the periodic table

In more detail…In more detail…

Scenario…. Produce a magazine article for a forensic science magazine. Make a title page with …A title (e.g. ‘All about atoms’)

• A logo used on the title page and also every other page

• ‘South West edition’ or similar to show that it’s a local periodical

• Date• Price

P1 • Using diagrams, describe the atomic / electronic structures of the first 20 atoms of the periodic table

• State the number of protons, neutrons and electrons for each atom

• Define isotopes. Draw and describe the 2 atoms of chlorine, showing the number of protons, neutrons and electrons for each atom

M1 • Relate the number of electrons in the outer shells of group 1 and 7 to their group number. Describe how outer electrons are further from the nucleus as we go down the group

• Describe patterns and trends in group 1

• Students write a description of the practical to investigate the reactivity of group 7 elements

• Describe patterns and trends in group 7 from your results

D1 • Explain patterns and trends in group 7 according to their atomic structure

• Explain patterns and trends in group 1 according to their atomic structure

Page from Longman FND book 2 that will help…

P1 138 • Using diagrams, describe the atomic / electronic structures of the first 20 atoms of the periodic table

136 • State the number of protons, neutrons and electrons for each atom

137 • Define isotopes. Draw and describe the 2 atoms of chlorine, showing the number of protons, neutrons and electrons for each atom

M1

140 • Relate the number of electrons in the outer shells of group 1 and 7 to their group number. Describe how outer electrons are further from the nucleus as we go down the group

152 • Describe patterns and trends in group 1

153 • Students write a description of the practical to investigate the reactivity of group 7 elements

156 • Describe patterns and trends in group 7 from your results

D1 • Explain patterns and trends in group 7 according to their atomic structure

• Explain patterns and trends in group 1 according to their atomic structure

Example…Example…

• Need a scanned example…