year 12 summer chemistry knowledge enhancement project ......year 12 summer chemistry knowledge...

24
Year 12 Summer Chemistry Knowledge Enhancement Project 1 Year 12 Chemistry Welcome to the start of your chemistry A-level journey. The next two years will be both challenging and rewarding. Provided you are willing to put in the effort, you will even have fun! Year 12 is a huge step up from GCSE, not only academically in terms of the content covered, but also the amount of work. It is achievable, provided you keep on top of the work. You will be expected to work hard in lessons. You will be expected to work even harder outside of lessons. Typically we suggest that for every one hour lesson, you do an extra 1 hour of self-directed learning. With 9 hours of timetabled lessons a fortnight, you should expect to devote a minimum of 18 hours a fortnight to Chemistry. Success requires on good time and workload management and whilst you will be helped with this along the way, ultimately it is your responsibility. The chemistry teachers are: Mr Carter (TCR) - Lab S11 [email protected] Miss Davis (SDV) - Lab S9 [email protected] Remember that support is always available. You must ask for help, don’t sit and struggle quietly. We are very approachable and always happy to see you between lessons. If not, drop us an email. The course specification we use is: OCR Chemistry A We look forward to meeting you in September. Mr Carter and Miss Davis Summer Subject Enhancement Project To give you a head start we have set an assignment that is to be competed throughout the summer holidays. Firstly, it will help enhance your chemistry knowledge in preparation for Year 12. Secondly, it will help you prove to us that you are academically capable, able to work independently and willing to put in the high level of effort that is expected. Please bring the completed assignment along to your first chemistry lesson. If you are unsure of what we asking, please email Mr Carter ([email protected]). This pack contains all the task instructions. It also contains a suggested book list. You will be given a course textbook on enrolment. Whilst the books on the list are not essential, they come with great recommendation from previous students. They are exam board specific and would be a great support tool to use alongside the textbook during self-directed learning.

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Page 1: Year 12 Summer Chemistry Knowledge Enhancement Project ......Year 12 Summer Chemistry Knowledge Enhancement Project 1 Year 12 Chemistry Welcome to the start of your chemistry A-level

Year 12 Summer Chemistry Knowledge Enhancement Project

1

Year 12 Chemistry

Welcome to the start of your chemistry A-level journey. The next two years will be

both challenging and rewarding. Provided you are willing to put in the effort, you will

even have fun! Year 12 is a huge step up from GCSE, not only academically in terms

of the content covered, but also the amount of work. It is achievable, provided you keep

on top of the work.

You will be expected to work hard in lessons. You will be expected to work even

harder outside of lessons. Typically we suggest that for every one hour lesson, you

do an extra 1 hour of self-directed learning. With 9 hours of timetabled lessons a

fortnight, you should expect to devote a minimum of 18 hours a fortnight to

Chemistry. Success requires on good time and workload management and whilst

you will be helped with this along the way, ultimately it is your responsibility.

The chemistry teachers are:

Mr Carter (TCR) - Lab S11 – [email protected]

Miss Davis (SDV) - Lab S9 – [email protected]

Remember that support is always available. You must ask for help, don’t sit and

struggle quietly. We are very approachable and always happy to see you between

lessons. If not, drop us an email.

The course specification we use is: OCR Chemistry A

We look forward to meeting you in September.

Mr Carter and Miss Davis

Summer Subject Enhancement Project

To give you a head start we have set an assignment that is to be competed

throughout the summer holidays. Firstly, it will help enhance your chemistry

knowledge in preparation for Year 12. Secondly, it will help you prove to us that you

are academically capable, able to work independently and willing to put in the high

level of effort that is expected. Please bring the completed assignment along to your

first chemistry lesson. If you are unsure of what we asking, please email Mr Carter

([email protected]).

This pack contains all the task instructions. It also contains a suggested book list.

You will be given a course textbook on enrolment. Whilst the books on the list are

not essential, they come with great recommendation from previous students. They

are exam board specific and would be a great support tool to use alongside the

textbook during self-directed learning.

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The assignment tasks are as follows:

1. Read the attached learning contract. Please sign it, get your parents/guardian

to sign it, and return it with your assignment during the first lesson.

2. Create a revision guide on The Foundations to AS Chemistry. Details are on

the following pages.

3. This is the exact exam paper that you will sit over the course of the first two

weeks at sixth form. It is up to you how much preparation you put in, but your

results in this exam will help inform our assumptions of your academic ability.

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Task 1: Complete Learning Contract AS/A2 Chemistry – Learning contract

Student Name:_______________________

Homework policy

Students will be set a minimum of 1 hour homework for each hour of directed

learning. A record will be kept of any missed deadlines or partially completed

work. This will allow teaching staff to monitor the student’s independent

commitment to their learning.

Students will be required to use the calendar of learning provided to read the

relevant pages of the textbook before attending the lesson. This will include

completing the summary questions at the end of each double page.

Assessment

Students will receive regular assessment. These will consist of questions taken

from past exam papers. They will be given at the end of each sub-topic and

marks will be recorded. The results will be analysed to identify areas requiring

additional targeted learning and revision.

Students will be asked to take a test in timed, exam conditions at least once

every half term

Revision

Lesson time will be allocated to revision of key content and exam techniques. At

exam time, homework’s will be given over to revision materials and past paper

questions. Teachers will review each other’s modules to ensure a range of

teaching strategies.

Signed:

_____________________ Chemistry department

_____________________ Student

______________________ Parent/Guardian

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Task 2: Revision guide on Foundations to AS Chemistry

You are to produce a revision guide on The Foundations to AS Chemistry. The

format to the revision guide is up to you; however, you must be able to hand in a

high quality piece of work on the first day. ChemGuide

(http://www.chemguide.co.uk/) is a very useful resource. Also take a look at the

suggested Book List in this pack. Your guide should cover the topics below. Your

work should be able to answer the related questions:

1. The structure of the Atom

a. What is the structure of an atom?

b. What is the relative charge and mass of each sub-atomic particle?

c. What is the difference between Atomic Number and Mass Number?

d. What are Isotopes?

e. Why is the Relative Atomic Mass for chlorine not a whole number?

f. How do you calculate Relative Formula Mass?

g. What the mole?

h. What equations links the number of moles; mass of a substance; and

Relative Atomic Mass?

i. How are electrons arranged in an atom?

2. Chemical Bonds: Ionic and Covalent Structures

a. What is ionic bonding?

b. How are ionic compounds formed?

c. What are the physical properties of ionic structures?

d. What is covalent bonding?

e. How are covalent compounds formed?

f. What are the physical properties of simple covalent and giant covalent

structures?

g. What are Groups and Periods in the Periodic Table?

3. Hydrocarbon Molecules

a. What are Hydrocarbons?

b. What is fractional distillation?

c. What happens with the combustion of hydrocarbons?

d. What are alkanes?

e. What are alkenes?

f. What is polymerisation?

g. What is cracking?

4. Rates of Reaction

a. What is meant by Rate of Reaction?

b. How can we measure the rate of a reaction?

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c. What effects the rate of a reaction?

5. Reversible Reactions

a. What is a reversible reaction?

b. What is equilibrium?

c. What is meant by Yield, and how can it be changed in a reversible

reaction?

6. Symbol Equations

a. How do you balance a chemical equation?

7. Calculating Formulae

a. What is the difference between empirical formula and molecular

formula?

b. How do you calculate empirical formulae?

8. Reactivity and The Periodic Table

a. How are elements arranged in the periodic table?

b. What are the trends in reactivity and properties in the Period Table

(especially groups I, II, VII)?

9. Chemical Reactions

a. What is Addition?

b. What is Dehydration?

c. What is Displacement?

d. What is Disproportionation?

e. What is Addition?

f. What is Hydrogenation?

g. What is Neutralisation?

h. What is Oxidation?

i. What is Reduction?

j. What is REDOX?

k. What is Precipitation?

l. What is Substitution?

m. What is Thermal Decomposition?

10. Energy and Chemistry

a. What is an exothermic reaction?

b. What is an endothermic reaction?

c. How do they relate to breaking & making bonds?

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Suggested Book List

You will be given a course textbook on enrolment. Whilst the books on the list are

not essential, they come with great recommendation from previous students. They

are exam board specific and would be a great support tool to use alongside the

textbook during self-directed learning.

Calculations in AS / A Level Chemistry

Jim Clark

Publisher: Longman

ISBN-13: 978-0582411272

Head Start to AS Chemistry

Richard Parsons

Publisher: CGP

ISBN-13: 978-1847621160

AS Level Chemistry for OCR A: Student Book

Richard Parsons

Publisher: CGP

ISBN-13: 978-1847627933

A2 Level Chemistry for OCR A: Student Book

Richard Parsons

Publisher: CGP

ISBN-13: 978-1847627940

AS-Level Chemistry OCR A Complete Revision & Practice

Richard Parsons

Publisher: CGP

ISBN-13: 978- 1847621269

A2-Level Chemistry OCR A Complete Revision & Practice

Richard Parsons

Publisher: CGP

ISBN-13: 978-1847622679

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Task 3: Exam Paper Preparation

This is the exact exam paper that you will sit over the course of the first two weeks at

sixth form. It is up to you how much preparation you put in, but your results in this

exam will help inform our assumptions of your academic ability.

(Periodic table included at the end)

1. (a) The diagrams represent the atomic structures of two gases, hydrogen and helium.

Hydrogen gas is made up of diatomic molecules (molecules with two atoms).

Helium gas exists as single atoms.

(i) How is a molecule of hydrogen formed from two hydrogen atoms?

(You may use a diagram as part of your answer)

..........................................................................................................................

.

..........................................................................................................................

.

..........................................................................................................................

. (2)

(ii) Why does helium exist only as single atoms?

..........................................................................................................................

.

..........................................................................................................................

.

..........................................................................................................................

. (2)

x = an electronp = a protonn = a neutron

2p2n

hydrogen helium

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(b) Hydrogen combines with carbon to form methane.

Each molecule contains four hydrogen atoms strongly bonded to a carbon atom.

Explain why methane has a low boiling point.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

(Total 6 marks)

2. In 1999 scientists at the University of Berkeley claimed to have discovered the element

Ununhexium.

The electron arrangement of this element is thought to be as shown in the diagram below.

H

H

H

C

H

H

H

H

H

C

H

H

H

H

H

C

H

H

H

H

H

C

H

H

C

H

H

H H

structural formulaof methane CH4

methane molecules

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(a) Which group of the periodic table should this element be placed in?

Group ............................. (1)

(b) Give a reason for your answer.

..........................................................................................................................

.................................................................................................................................. (1)

(Total 2 marks)

3. The diagram shows part of the ionic lattice of a sodium chloride crystal.

(i) Complete the spaces in the table to give information about both of the ions

in this lattice.

Name of ion Charge

..................................................... .....................................................

..................................................... .....................................................

(2)

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(ii) When it is solid, sodium chloride will not conduct electricity. However,

molten sodium chloride will conduct electricity. Explain this difference.

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (2)

(iii) Complete the sentence.

Sodium chloride conducts electricity when it is molten and when it is

.......................................................................................................................... (1)

(b) The symbol for a calcium atom can be shown like this:

(i) What is the mass number of this atom?

.......................................................................................................................... (1)

(ii) What information is given by the mass number?

..........................................................................................................................

.......................................................................................................................... (1)

Ca40

20

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(c) Calcium burns in oxygen with a brick-red flame. The product is a white solid. It is

calcium oxide and its formula is CaO.

(i) Balance the chemical equation for the reaction.

Ca(s) + O2(g) CaO(s)

(1)

(ii) Describe, in terms of electrons, what happens to a calcium atom when it

becomes a calcium ion.

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (2)

(Total 10 marks)

4. (a) Copper is a metal.

Explain how it conducts electricity.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

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(b) Graphite is a non-metal.

Use the information to explain why graphite conducts electricity.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (3)

(Total 5 marks)

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5. Distress flares are used to attract attention in an emergency.

Flares often contain the element magnesium. Magnesium burns to form magnesium

oxide.

(a) The distress flare burns with a bright flame because the reaction is very

exothermic.

State the meaning of exothermic.

.....................................................................................................................................

..................................................................................................................................... (1)

(b) Write a balanced symbol equation for the reaction between magnesium (Mg) and

oxygen (O2) to form magnesium oxide (MgO).

..................................................................................................................................... (1)

(c) The diagram shows the electronic structure of a magnesium atom.

The atomic (proton) number of magnesium is 12.

Magnesium atom

Draw a similar diagram to show the electronic structure of an oxygen atom.

The atomic (proton) number of oxygen is 8. (1)

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(d) Magnesium ions and oxide ions are formed when magnesium reacts with oxygen.

The diagram shows the electronic structure of an oxide ion.

Oxide ion

Draw a similar diagram to show the electronic structure of a magnesium ion.

(1)

(e) Magnesium oxide is a white solid with a high melting point.

Explain how the ions are held together in solid magnesium oxide.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

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(f) Indigestion tablets can be made from magnesium oxide. The magnesium oxide

neutralises some of the hydrochloric acid in the stomach.

Complete the word equation for the reaction between magnesium oxide and

hydrochloric acid.

hydrochloric acid magnesium oxide ...................... water. (1)

(Total 7 marks)

6. Crude oil is a mixture of mostly alkanes.

(a) Crude oil is separated into useful fractions by fractional distillation.

(i) Describe and explain how the mixture of alkanes is separated by fractional

distillation.

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (3)

(ii) The table gives the name and formula for each of the first three alkanes.

Complete the table to show the formula of butane.

Name of alkane Formula

Methane CH4

Ethane C2H6

Propane C3H8

Butane

(1)

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(b) The structural formula of methane, CH4, is:

H

H C H

H

Draw the structural formula of propane, C3H8

(1)

(c) The relative amounts of and the market demand for some hydrocarbons from the

fractional distillation of crude oil are shown in the graph.

(i) Why is the market demand for the C5 – C8 fraction higher than the market

demand for the C21 – C24 fraction?

..........................................................................................................................

.......................................................................................................................... (1)

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(ii) Cracking is used to break down large hydrocarbon molecules into smaller

hydrocarbon molecules.

Complete the symbol equation by writing in the formula of the other

hydrocarbon.

C20H42 C16H34 2 ..........................................

(1)

(iii) The C5 – C8 fraction has low supply and high market demand.

Suggest three ways in which the oil industry could overcome this problem.

1 .........................................................................................................................

..........................................................................................................................

2 ................................................................................................................

..........................................................................................................................

3 .......................................................................................................................

.......................................................................................................................... (3)

(Total 10 marks)

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7. (a) The diagram shows the electronic structure of a particular element.

In a similar way, show the electronic structure of another element from the same

group in the periodic table and name the element you select.

Name of element selected ..........................................................................................

(4)

x

x

x x

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(b) The element lithium gives a moderate reaction with cold water, releasing hydrogen

and forming a solution of lithium hydroxide.

Describe how sodium is similar to and how it is different from lithium in its

chemical reaction with cold water.

Explain any similarity or difference in terms of their atomic structure.

Similarity. ..................................................................................................................

Reason. ......................................................................................................................

....................................................................................................................................

....................................................................................................................................

Difference. .................................................................................................................

Reason. ......................................................................................................................

....................................................................................................................................

.................................................................................................................................... (5)

(Total 9 marks)

8. Ammonia is produced by the Haber process. In the process nitrogen and hydrogen are

mixed. The pressure is increased to about 200 atmospheres. The gases are passed over

an iron catalyst at about 450°C. The equation for the reaction is:

N2(g) + 3H2(g) 2NH3(g)

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The reaction between nitrogen and hydrogen is reversible. This affects the amount of

ammonia that it is possible to obtain from the process. The graph below shows how the

pressure and temperature affect the percentage of ammonia that can be produced.

Use this information, together with your knowledge of the process, to explain why many

industrial ammonia plants operate at 200 atmospheres and 450°C.

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

............................................................................................................................................... (Total 5 marks)

4003002001000

10

20

30

40

50

60

70

%ammoniaproduced

pressure (atm)

80

350ºC

400ºC

450ºC

500ºC

550ºC

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9. The monomer chloroethene is made from ethene in a two-stage process,

(a) The first stage is to convert ethene to 1,2-dichloroethane.

2C2H4(g) + 4HC1(g) + O2(g) 2C2H4Cl2(g) + 2H2O(g)

ethene 1,2-dichloroethane

State and explain the effect of increasing the pressure on:

(i) the yield of 1,2-dichloroethane;

..........................................................................................................................

.

..........................................................................................................................

. (2)

(ii) the rate of reaction.

..........................................................................................................................

.

..........................................................................................................................

. (2)

(b) In the second stage 1,2-dichloroethane is converted into chloroethene.

C2H4C12 C2H3C1 + HCl

This reaction is a thermal decomposition.

Suggest what would need to be done to decompose 1,2-dichloroethane.

.....................................................................................................................................

.

.....................................................................................................................................

. (1)

(Total 5 marks)

10. Methanol (CH3OH) can be made by reacting methane (CH4) and oxygen (O2) in the

presence of a platinum catalyst. The reaction is exothermic.

An equation that represents the reaction is:

2CH4 + O2 2CH3OH

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(a) The energy level diagram for this reaction is given below.

(i) Use the diagram to explain how you know that this reaction is exothermic.

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (1)

(ii) Explain, in terms of the energy level diagram, how the platinum catalyst

increases the rate of this reaction.

..........................................................................................................................

.......................................................................................................................... (1)

(b) The equation can also be written showing the structural formulae of the reactants

and the product.

Energy

2CH + O

2CH OH

24

3

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(i) Use the bond energies given in the table to help you to calculate the energy

change for this reaction.

Bond Bond energy in kJ

C –– H 435

O = O 498

C –– O 805

O –– H 464

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

Energy change = ...................................... kJ (3)

(ii) In terms of the bond energies, explain why this reaction is exothermic.

..........................................................................................................................

.......................................................................................................................... (1)

(Total 6 marks)

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