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Year 10 Science Topic: Materials

Metals as MaterialsAchievement Objectives

Achieved Merit Excellence

1. Naming different materials.

2. carrying out a range reactions to observe physical and chemical properties of selected metals.

3. describe reactivity with oxygen, water and acids.

4. describe the properties and uses of metals.

5. using chemistry vocabulary, symbols.

6. completing word equations.

7. gathering primary data about rusting of iron.

Practical Skills8. Using a triple-beam

balance.9. using a measuring

cylinder.

1. Linking the properties of metals and their uses.

2. order metals in a series based on their reactivity.

3. linking the uses of metals to their reactivity with oxygen, water, and other chemicals.

4. using a range of chemistry vocabulary and symbols.

5. writing word equations.6. gathering quality primary

data, processing and interpreting primary data about rusting of iron.

1. Discuss the use of selected metals in everyday life.

2. linking the occurrence of metals to their reactivity.

3. writing balanced symbol equations.

4. processign and interpreting primary or secondary data about conditions that affect usefulness of metals.

Metals as MaterialsAchievement Objectives

Achieved Merit Excellence

10. Naming different materials.

11. carrying out a range reactions to observe physical and chemical properties of selected metals.

12. describe reactivity with oxygen, water and acids.

13. describe the properties and uses of metals.

14. using chemistry vocabulary, symbols.

15. completing word equations.

16. gathering primary data about rusting of iron.

Practical Skills17. Using a triple-beam

balance.18. using a measuring

cylinder.

7. Linking the properties of metals and their uses.

8. order metals in a series based on their reactivity.

9. linking the uses of metals to their reactivity with oxygen, water, and other chemicals.

10.using a range of chemistry vocabulary and symbols.

11. writing word equations.12.gathering quality primary

data, processing and interpreting primary data about rusting of iron.

5. Discuss the use of selected metals in everyday life.

6. linking the occurrence of metals to their reactivity.

7. writing balanced symbol equations.

8. processign and interpreting primary or secondary data about conditions that affect usefulness of metals.


Lesson 1: Many different types of meterials we use in everyday life.

Class Activity

Classify these materials into two different groups (Categories).

Copper, Aluminium, Zinc, Iron, Gold, Silver, Mercury, Oxygen, Chlorine,

Sulfur, Nitrogen, Neon, Helium

Metals Non-Metals

Class Activity

(1)Write down 5 uses of metals in the classroom

(2)Write down 5 uses of non-metals at home.


Science Nation - Metal Foam: http://www.youtube.com/watch?v=wfFcs25KmMcproperties of lead: http://www.youtube.com/watch?v=ibzHnVRrroI&feature=relatedLead poisoning: http://www.youtube.com/watch?v=EGac6S0NLXk&feature=relmfu

http://www.youtube.com/watch?v=EGac6S0NLXk&feature=relmfu

http://www.youtube.com/watch?v=EGac6S0NLXk&feature=relmfu

http://www.youtube.com/watch?v=ibzHnVRrroI&feature=related

http://www.youtube.com/watch?v=ibzHnVRrroI&feature=related

http://www.youtube.com/watch?v=wfFcs25KmMc

http://www.youtube.com/watch?v=wfFcs25KmMc


Metal objects are usually strong, shiny and can be bent without breaking.

Most metals are found as ores (=metal compounds). These ores are smelted to extract the pure metal.

A pure metal is an element.Element is a pure substance and is made up of one kind of atom.

Sometimes another element is mixed into a molten metal to give an alloy. Eg. Nickel + Aluminium + Copper gives gold coins.

Lesson 2: Physical Properties of Metal


Materials can be divided into many groups based on chemical and physical properties.

Metals as a material

Metals have many aspects of their appearance and the way that they act that make each metal similar to the others. We call these similarities physical properties.

Because we can group metals together as being similar elements, they are placed together on the periodic table. Metals can be found on the left hand side of the periodic table.

Of the 109 known elements, at least 80 are metals. Most have common


features such as:

They conduct electricity They conduct heat Lustre (shiny) when cleaned. They are malleable (can be bent and hammered without

breaking). They are ductile (can be pulled out into wires). Are solids (except mercury).


PHYSICAL PROPERTIESAll metals have certain physical properties, which they have in common. The most obvious of these is their appearance. They are usually a grey colour with the exception of copper (which is usually referred to as pink) and gold (which as a yellow colour). If a metal is polished or freshly cut, it will also have a lustre or shininess. All metals are in a solid state at room temperature with the exception of mercury, which is the liquid metal used in thermometer.

Metals also have the ability to be reshaped easily. They can be bent into different shapes or hammered out into a sheet without the metal breaking. We call this ability to reshape, malleability.

Another property that all metals have in common is their ability to be stretched out into wires, once again, without breaking. We call this ability to stretch, ductility. Metals are often used to make bells and this is because they are sonorous. When we hit a metal with another hard object, it makes a ringing sound.


The physical properties of metals can be summarised as follows:

Lustre Malleable Ductile Sonorous Conductors of heat and electricity Usually grey – except copper and gold Usually solids at room temperature – except mercury

Activity

Draw a table to show comparison of metal and non-metal’s physical properties.

PHYSICAL PROPERTIES METAL NON-METALAppearance

StateColourDensity

MalleabilityDuctile

Thermal (heat) conductivity

Electrical conductivity


PHYSICAL PROPERTIES METAL NON-METAL

Appearance Shiny when freshly cut Dull

State Solid at room temperature.Except ______.

Gas (or liquid like bromine)

Colour Silvery whiteExcept ______ and _____

Density High* _____ and ____ are light metals. Low

MalleabilityMalleable

Can be _____ into different shapes without breaking.

Brittle.Break or shatter when

hammered.

Ductile DuctileCan be drawn out into ____. Not ductile

Thermal (heat) conductivity Good Poor

Electrical conductivity good Poor

Except ____

HomeworkPg86 Q4: The word puzzle

Lesson 3: Practical Lesson


Experiment 1:

Measuring Density of different metalsAim: To find out the density of some common metals.

Method: 1. Check a metal cube (ie. Fe = Iron)2. Measure the length of one side. Find the volume.

Volume (cm3)= s x s x s

3. Measure the mass of the cube. Use the triple beam balance.

4. Find the density of iron.

Result: Record in the table below.Material

(name of the metal) Mass(g) Volume (cm3) Density g/ cm3

Conclusion: ____________________________________________________

__________________________________________________________________

HomeworkPg87 Q5: Copy and complete the chart which summarises the properties of some metals, then answer the questions below. The term ‘atom mass’ refers to the mass of an atom compared to a hydrogen atom..

Lesson: Practical Lesson


Experiment 2:

Electrical conductivity of common metals

H.O.M: Aim: To find out electrical conductivity of common metals..

Method: using the electrical conductivity apparatus provided, test whether the metal will conduct electricity.

Results:Name of material

Metal or Non metal

Electrical Conductor or Insulator

Graphite(carbon)

Non- Metal conductor

Aluminium Metal Conductor

Copper Metal Conductor

Rubber Non-metal Insulator

Wood Non-metal Insulator

Plastic Non-metal Insulator

Iron metal conductor

Conclusion:

Metals are good conductors of electricity. Non-metals are poor

conductors of electricity, except graphite.

Metal properties and atoms (pg 85)


HomeworkPg86 Q3: Decide whether the following statement are true or false

Demonstration


Experiment 3:

Thermal conductivity of common metals

Aim: To find out thermal conductivity of common metals..

Method: using the thermal conductivity apparatus provided, test whether the metal will conduct electricity.

Results:Name of material Thermal Conductor / Insulator

Conclusion: ____________________________________________________

__________________________________________________________________

Lesson: Uses of metals


Relating Metal properties to their uses

Metal Symbol Uses Property Involved

Copper

Aluminium

Mercury

Lead

Zinc

Tin

Silver

Gold

Iron

Metal Symbol Uses Property Involved


Copper Cu Pipes, Wires, Cooking pots

Unreactive with air and water

Excellent electrical conductor

Good thermal conductor

Aluminium Al Aircraft frames,

wires

Strong, light/weight / unreactive

Good conductor / ductile

Mercury Hg Thermometres Expands regularly with heat

Lead Pb Roof flashing, fishing sinkers

Soft/ very malleable Very dense

Zinc Zn Galvanising(coating with Zn)

Forms a protective coating

Tin Sn Tin coating Unreactive with air and water

Silver Ag Jewellery Malleable/ lustrous/ unreactive

Gold Au Jewellery Malleable/ lustrous/ unreactive

Iron Fe Car bodies,Structural steel.

Forms a strong alloys / malleable and flexible.

HomeworkPg86 Q2: Identify each of the metals used below, and state property of that metal which is related its use.

Activity

Decide whether the following statements are true or false.


1.Metals will usually snap when they are bent.2.The surfaces of most metals are shiny when

freshly cut.3.All metals have high melting points making

them solids at room temperature.4.Aluminium is lightweight, strong metal.5.Copper is used in cooking pots as it is a good

thermal conductor.6.Aluminium is used in galvanising.


ANSWERS:

Decide whether the following statements are true or false.

1. Metals will usually snap when they are bent. F

2. The surfaces of most metals are shiny when freshly cut.

T

3. All metals have high melting points making them solids at room temperature. F

4. Aluminium is lightweight, strong metal. T

5. Copper is used in cooking pots as it is a good thermal conductor. T

6. Aluminium is used in galvanising. F

Pg 86 - 87Complete Question 1,2,3,6,7

Metal Reactions


Metal + other reactant Product

The three important chemical properties of metals are how they react with water, oxygen and acids.

1. Metal + Oxygen Metal oxide2. Metal + water Metal hydroxide + Hydrogen gas3. Metal + acids Salt + Hydrogen gas

(1) Metals and Oxygen

When an alkali metal reacts with oxygen in air, an oxide is produced.Metal + Oxygen Metal oxide

Oxygen gas is an extremely reactive chemical and readily combines with most other chemicals. When oxygen combines with another substance the reaction is called oxidation.

Slow oxidation occurs at ordinary temperatures and produces no light or heat. Eg. Rusting, tarnishing

Fast oxidation produces lots of heat and light. This is called combustion. Only a few very reactive metals burn really easily, such as Magnesium and Sodium.

Experiment :

Combustion of Magnesium


Magnesium is one of the most common elements in Earth’s crust. In its pure form, it is silvery white, and relatively soft. It is often used in fireworks. Warning: Burning magnesium produces some ultraviolet light. Avoid looking directly at it.

Aim: To find out how magnesium reacts with oxygen during the combustion.

Equipment: Magnesium ribbon, Bunsen burner, tong, safety mat

Method: 1. Prepare a strip of magnesium ribbon about 2cm long.2. Set up a Bunsen burner.3. Use a tong to hold the strip of magnesium ribbon.4. Put the magnesium ribbon into the flame to start the

combustion reaction.5. Record any changes.

Result: ____________________________________________

Conclusion: _______________________________________

Magnesium + Oxygen __________ ___________

http://www.schoolsnet.com/pls/hot_school/sn_lessons.page_pls_lesson_detail?x=16180339&p_lesson_id=61&p_res_type_id=15

(2) Metals and water




Metal + Water Metal hydroxide + Hydrogen gas

Some metal reacts with water, especially hot water or steam.

Copper is used for hot water pipes because it does not react with hot water.

Not all metals react with cold water. Some metals only react slowly react more quickly with hot water or steam.

Reaction of metals with water:React with hot water

React with steam

No reaction with water

Reaction with cold water

Magnesium Aluminium, Zinc, Iron

Tin, Lead, Copper, Silver,

Gold

Sodium, Lithium, Calcium

Observation of Water and Metal reaction:Metal Action in waterSodium, Calcium Strong bubbling in cold waterMagnesium Gas given off in hot waterAluminium, Zinc Bubbling in steamIron, Lead Slow bubbling in hot waterCopper, Silver, Gold No reaction

Demonstration :

Sodium metal in water


Warning: Must wear safety glasses as the experiment involves fire and small explosion.

Sodium is a very reactive metal which must be handled with care. Sodium is usually kept under mineral oil to keep it from reacting with oxygen or water in the atmosphere.

Aim: To observe the reaction of sodium metal in cold water.

Method: 1. ________________________________________________

2. ________________________________________________

3. ________________________________________________

Result: ____________________________________________

Conclusion: _______________________________________

Sodium + Water _______ ________ + _____ + heat

Discussion: Sodium reacts with water to form Sodium Hydroxide and Hydrogen Gas. The reaction produces a lot of heat, which is sufficient to melt the metal if enough of it is used. The molten metal may start to boil and break apart. This speeds up the reaction rate due to the increase in surface area. Then the hydrogen gas is ignited and explosion occurs.

The energy produced during the reaction causes sodium metal to catch on fire.

Questions

1. Write word equations to describe the reactions of the


following metals with steam.

(a) Iron:Iron + water iron hydroxide + hydrogen gas

(b) Aluminium:Aluminium + water aluminium hydroxide + hydrogen

gas

(c) Zinc: Zinc + water zinc hydroxide + hydrogen gas

2. Why is copper used for hot water pipes?Copper does not react with water.

Year10 Science: Pg 90 Q1,3,7,8

Metal and Water Reaction & Metal and Acid Reaction

Wear safety classes


Aim:

Hypothesis:

Method:

Hydrogen gas testingPresence of hydrogen gas can be indicated by hydrogen gas burning with a “pop” or “squeak” sound when a flame is brought near it. You will be able to observe water droplets on the surface of the test tube.

Metal hydroxide is a base substance. Base substances turn red litmus paper into blue.

Result:

Conclusion:

Discussion:

Calcium + Water +

Calcium + Hydrochloric acid +

Questions1. Write word equations for the reaction between

(a) Zinc and hydrochloric acid

(b) Aluminium and hydrochloric acid

2. Complete the following table to show the salts formed when each metal reacts with each acid.

Metal Salts formed when metal reacts withHydrochloric acid Nitric acid Sulphuric acid


Magnesium

Aluminium

Zinc

Iron

Year10 Science: Pg 90 Q2, 4, 9

Corrosion and Rust1. Tarnish: Slow reactions of

metals with oxygen, water, carbon dioxide gas or other chemicals in the air. (Except


gold)

2. Corrosion: Wearing down of metals when exposed to air. Aluminium form a protective coating (Aluminium oxide) which prevents any further reaction.

3. Rusting: When iron is exposed to air a bright orange compound called rust forms on the surface. This is a gradual breakdown of iron objects. Rusting requires water and air.

4. Rust prevention methods: Painting, galvanising, plating, alloying, oil

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