Part A

Part A

Surname

Name

American Academy Larnaca

Year 3 Science

Semester 2

Test 2

Unit C1

Topic 4

Unit B1

Topic 3

Chemistry in our world

Obtaining and using metals

Influences on life

Problems of and solutions to a changing

environment

Part A

Time: 20 minutes

1. The list shows some metals in reactivity series order with the most reactive at the top.

Most reactive calcium magnesium aluminium zinc iron copper

Least reactive gold

(a) Which of these metals can be found as the uncombined metal in the Earth’s crust? Complete the sentence by putting a cross ( ) in the box next to your answer. (1)

A calcium B gold C magnesium D zinc

Aluminium is extracted by the electrolysis of a molten mixture of its ore (bauxite) and cryolite. Iron is extracted by heating a mixture of its ore and carbon. (b) Explain why electrolysis is used to extract aluminum but is not used to extract iron. (2)

_____________________________________________________________________________ _____________________________________________________________________________

(c) Iron oxide reacts with carbon monoxide to form iron and carbon dioxide. The equation for the

reaction is:

Fe2O3 + 3CO � 2Fe + 3CO2 State what happens to iron oxide (Fe2O3) and to carbon monoxide (CO). (2) _____________________________________________________________________________ _____________________________________________________________________________

[Total marks for Q1 = 5]

2. An alloy of aluminium with magnesium is used for parts of aeroplanes.

(a) State the meaning of the term alloy. (1) _____________________________________________________________________________

(b) Explain why the aluminium alloy is stronger than pure aluminium. (2)

_____________________________________________________________________________ _____________________________________________________________________________

(c) (i) When aluminium corrodes, it reacts with oxygen to form aluminium oxide, Al2O3. Complete the equation (including balancing) by putting numbers in the spaces provided.

4 Al + _____O2 � _____Al2O3 (2)

(ii) Name the reaction that takes place for the equation above. (1)

___________________________________________________________________________

[Total marks for Q2 = 6]

3. Many everyday items are made of metal.

For example, electrical wires are made of copper.

(a) Give a property of copper that makes it suitable for this use. (1)

_____________________________________________________________________________

(b) Explain why gold is a suitable metal to make jewellery. (2)

_____________________________________________________________________________ _____________________________________________________________________________

[Total marks for Q3 = 3]

Disease

4. (a) Smoking tobacco is the cause of 9 out of 10 cases of lung cancer.

(i) Complete the sentence by putting a cross ( ) in the box next to your answer. The active compound in cigarette smoke that causes lung cancer is (1)

A carbon dioxide B carbon monoxide C nicotine D tar

(ii) One part of cigarette smoke acts on receptor sites in the brain. Explain why it can be very difficult to give up smoking. (2) ________________________________________________________________________ ________________________________________________________________________

(b) Smoking cigarettes can have an effect on reaction times. State the group of drugs which increase the speed of reactions. (1) _____________________________________________________________________________

(c) Cigarette smoke contains carbon monoxide.

Explain the effect of breathing in carbon monoxide on the function of the blood. (2) _____________________________________________________________________________

_____________________________________________________________________________

_____________________________________________________________________________

[Total marks for Q4 = 6]

Part B

Part B

Surname

Name

American Academy Larnaca

Year 3 Science

Semester 2

Test 2

Unit B1

Topic 3

Unit P1

Topic 5

Topic 6

Influences on life

Problems of and solutions to a changing

environment

Universal Physics

Generation and transmission of

electricity

Energy and the future

Part B

Time: 20 minutes

FORMULAE

You may find these formulae useful

electrical power = current × potential difference P = I × V

cost of electricity = power × time × cost of 1 kilowatt-hour

Do not forget to include units in all your answers

1. Fetal alcohol syndrome occurs when a pregnant woman drinks large quantities of alcohol. The diagram shows the development of the embryo and fetus during its time in the uterus. The bars show the time period during which fetal alcohol syndrome can cause an abnormality in a specific body part. The darker the bar, the more likely an abnormality will occur in that body part.

(a) (i) Complete the sentence by putting a cross ( ) in the box next to your answer. The body part most likely to be affected by fetal alcohol syndrome throughout pregnancy is the

(1) A central nervous system B heart C arms D eyes

(ii) State the period of time when a defect in the development of the legs is most likely to occur. (1)

___ __________________________________________________________________________

(b)(i) Alcohol is a drug. Define the term drug. (1) _____________________________________________________________________________ _____________________________________________________________________________ (ii) Explain why alcohol is classed as a depressant. (1)

_____________________________________________________________________________ _____________________________________________________________________________

(c) (i) Describe a long-term effect of alcohol abuse. (2)

_____________________________________________________________________________ _____________________________________________________________________________

(ii) Discuss the ethics of allowing alcoholics to have an organ transplant. (2)

_____________________________________________________________________________ _____________________________________________________________________________

[Total marks for Q1 = 8]

2. Some students carry out investigations with an electric motor.

The diagram represents the energy transfers in the electric motor.

(i) How much energy is wasted? (1)

wasted energy = J __________

(ii) Calculate the efficiency of the motor. (2)

efficiency = __________

[Total marks for Q2 = 3]

3. Transformers are used on a small scale in the home and on a large scale in the National Grid.

(i) The transformer for an electric toothbrush charger steps down the mains voltage to 9.0 V.

The mains voltage is 230 V. The transformer has 690 turns on its primary coil. Calculate the number of turns on the secondary coil. (3)

number of turns = __________

*(ii) The National Grid transmits electricity around the country. Explain how using transformers makes the transmission of electrical energy more efficient. (6) ___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________ ___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

[Total marks for Q3 = 9]

Mark scheme Part A

Question Number

Answer Acceptable answers

Mark

1(a) B gold 1

1(b)

2

1(c) Fe2O3 is reduced (1) CO is oxidised (1)

CO gains oxygen 2

2(a)

1

2(b)

2

2(c)(i)

4Al + 3O2 � 2Al2O3

3 (1) 2 (1)

2

2(c)(ii) oxidation (1) 1

3(a)

1

3(b)

2

Question Number

Answer Acceptable answers

Mark

4(a)(i) D (1)

(a)(ii) An explanation linking the following points • nicotine (1) • addictive / causes you to want more (1) • as the receptor sites in the brain become more used to the nicotine it has less effect / increased amounts are needed for the same effect (1)

makes you crave it

(2)

(b) stimulants Accept any reasonable spelling of the term e.g. stimulents (1)

(c) An explanation linking two of the following points • carbon monoxide binds with red blood cells (1) • containing haemoglobin (1) • this reduces the oxygen carrying capacity of the blood (1)

accept blood for red blood cells Accept oxyhaemoglobin less oxygen is carried in the blood Accept references to carboxyhaemoglobin

(2)

Part B

Question Answer Acceptable answers

Mark

1a(i) A – central nervous system

(1)

1a(ii) 4 – 7 weeks Accept 4 ½ - 7 ½ 4 – 7 ½ 4 ½ - 7

(1)

1b (i) A definition including any two of the following: a chemical substance (1) has an effect on the body / nervous system / brain (1) causing psychological / physiological / behavioural changes (1)

causing changes in behaviour / addiction

(2)

1b(ii) Any one of the following:

• increases reaction times / slows down impulses / reactions(1)

• slows down the activity of the brain / nervous system (1)

• acts on neurotransmission /at the synapse (1)

(1)

1c(i) A description linking the following points:

• addiction / alcoholism (1)

• liver / brain /kidney damage (1)

• cirrhosis / cancer (1)

accept – other organ damage related to alcohol abuse but ignore lung damage

(2)

Question Answer Acceptable answers

Mark

1c(ii) A suggestion linking two of the following points:

• alcoholics have caused their liver to fail by their addiction (1)

• if alcoholics continue to drink, the organ could be damaged (1)

• other people may deserve the liver transplant more (1)

• addiction is an illness(1)

• everybody has a right to life (1)

alcoholics damage their own liver / people choose to be alcoholics it is not their fault they are addicted alcoholics may die if they do not get a transplant

(2)

2(i) 150 (J) 200 – 50 (J) 200 minus 50 (J) (1)

2(ii) substitution (1) 50 ÷ 200 (× 100%) evaluation (1) 25 (%)

0.25, 1/4 give (2) marks for correct answer, no working

(2)

3(i)

evaluation (1) 27

Accept either order for transformation / substitution give 2 marks for correct answer, no working

(3)

Indicative content Mark

3*(ii) Basic ideas • transformers change voltage and/or current • transformers use a.c. • the current warms the transmission wires • step-up transformers increase the voltage • step-up transformers decrease the current • energy is wasted Linked • power depends on both current and voltage • power = current × voltage (P = I × V) • at high voltage, the same power needs less current • correct mention of turns ratio related to (6)

voltage change • a smaller current in a wire produces less heat Including reasons • when you use a higher voltage, the current is lower. With lower current, the amount of heat produced is less. If less heat is lost, the efficiency is greater. • correct use of (P = I × V) to show that current is less in the transmission wires. Less heat is lost because the current is lower. If less heat is lost, the efficiency is greater. • current wastes heat in wires. Using a higher transmision voltage, and therefore a lower current, saves more energy in the transmission wire than is lost in the transformers

Level 0 no rewardable material

1 1-2 • basic relevant ideas, not linked and no explanation or reason • e.g. the current warms the transmission wires • the answer communicates ideas using simple language and uses limited scientific terminology • spelling, punctuation and grammar are used with limited accuracy

2 3-4 • detailed comments linking ideas • e.g. a smaller current in a wire produces less heat • the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately • spelling, punctuation and grammar are used with some accuracy

3 5 - 6 • full explanation with reasons • e.g. transformers are used to reduce the current so that the heat loss is less and efficiency is more • the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately • spelling, punctuation and grammar are used with few errors