Grade 8 Unit M.2 - Metals Grade 8 Metals · Using ICT: Search the net for some videos ... Lesson Reacting Metals with Air (oxygen): ... Grade 8 Unit M.2 - Metals 10

Grade 8 Unit M.2 - Metals

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Grade 8

Metals

Iron Ore, where we extract iron from!

Molten Metal

Mining for Copper

Aluminum!

Rusting!


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Standards:

13.1 Deduce a reactivity series for common metals based on their

reactions with air, oxygen, water and dilute acids.

13.2 Know that the test for hydrogen is that it explodes when mixed

with air and ignited.

13.3 Know that when metal reacts with air, oxygen or water, an oxide

or hydroxide is formed and that if this is soluble in water, the solution

is alkaline

13.4 Correctly place a metal in the reactivity series based on

experimental evidence.

13.5 Account for the anomalous behavior of aluminum in its reactions

with air, water and dilute acids.

13.7 Understand that reactive metals can displace less reactive ones

from their compounds.

Objectives: 1. Deduce a reactivity series for common metals based on their

reaction with air, water and diluted acids

2. Know that the test for hydrogen is that it explodes when mixed

with air and ignited

3. Know that the result of the reaction is the metal oxide or

hydroxide, which gives an alkaline solution.

4. Correctly place the metals in the reactivity series based on the

experimental evidence.


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KEY WORDS

Reactivity series

انتفبعهخ طهظخ

Acid حط

Base قبعذ

Electrolysis انكزثبئ انتحهم

Reactive يتفبعم أ شط

Dilute يخفف

Alkali قه


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There are many types of metals. Some metals are more chemically

active than others. One group of very active metals is the alkali

metals. They include lithium, sodium, potassium and others

The metals can be placed in order of

reactivity. The most reactive is at the

top, the least reactive at the bottom. ي اكثزشبطب انفهشاد ثعط. انفهشاد ي يختهفخ أاع بك

انفهشاد يجعخ شبطب انفهشاد أكثز ي. األخز االع

، انهثو يثم انعبصز تحت انجعخ ذ. انقهخ

عه اعتبدا انعبصز تتتز انك ي. انجتبطو انصدو،

. األطفم ف شبطب األقم انعبصز األعه ف تظع شبطب األكثز انعبصز. انشبطخ

Using ICT: Search the net for some videos (you can use Google

video; enter the key words 'reactivity series')

Reactivity Series:

If you take nine common metals and do a

series of different experiments with them

(like heat them in air, add water, add acid),

you will soon spot a pattern. The metal

that is dangerously violent in your first

experiment will always be the most

reactive in all of the other experiments.

Likewise, the slowest-reacting metal will

always be slow and un-reactive. This is called

the reactivity series. The top metal is the

most reactive and the order never changes. ، ااء ف ارغخ١ ص) ػ١ا اخرفح ارعاسب تغغح لد اشائؼح اؼاد ذغؼح أخزخ إرا

. رفاػالخ ػ ظد ذالؼع فغف ،( ؼاط إظافح ، ااء إظافح

ارعاسب ظ١غ ف شاغا األوصش دائا ٠ى األ ذعشتره ف تؼ١ف ارفاػ اؼذ ٠ى عف

. .اشاغ عغح ٠غ ا زا. افؼ سد ف تطء دائا ٠ى اؼاد أتطأ فإ ، تاص. ساألؾ

Figure 1: Set up of how metals will be

tested with acid.

Figure 2 Reactivity Series


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Reactivity series: list of metals in order or reactivity. اشاغ عغح

.ارفاػالخ ف اشاغ ذشذ١ة ؼغة لائح

Reacting Metals with Air (oxygen):

: اناء( األكظج) يع انعبد تفبعم

A typical example of the reactivity series is the reaction of metals in

air. Metals react in the air to form a metal oxide. اؼاد أوغ١ذ رشى١ ااء ف ذرفاػ اؼاد(. األوغع١) ااء غ ٠رفاػ اؼاد

Metal + oxygen Metal oxide (main equation)

Calcium + Oxygen calcium oxide (example)

2Ca (s) + O2(g) 2CaO(s)

Potassium, K

Potassium burns vigorously in oxygen. It gives a lilac flame to

produce an orange powder.

.ا تشذما غؽق أسظا ة ٠ؼط . األوغع١ ف تمج ٠ؽرشق اثذاع١

Potassium + Oxygen —> Potassium oxide

K(s) + O2 (g) —> KO2(s)

Sodium, Na

Sodium burns vigorously in oxygen, so only gently heating is

required to make it burn. It gives a golden yellow flame to

produce a white powder.

رث أصفش ة ٠ؼط .تذء ارغخ١ ٠ض ، األوغع١ ف تمج ٠ؽرشق اصد٠

.أت١ط غؽق

Lesson 4


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Sodium + Oxygen —> Sodium oxide 4Na (s) + O2

(g) —> 2Na2O(s)

Magnesium, Mg

Strong heating is required to make magnesium burn in oxygen.

to produce a white powder of magnesium oxide.

.اغ١غ١ أوغ١ذ أت١ط غؽق ٠رط. األوغع١ ف ااغ١غ١ رغخ١ ؽراض

Magnesium + Oxygen —> Magnesium oxide

2Mg(s) + O2 (g) —> 2MgO(s)

Iron, Fe

Strong heating is required to make iron powder burn in oxygen. The reaction gives

out a yellow showery sparks and produces a black solid.

.عداء صثح ادج اصفش ششس ٠ؼط . األوغع١ ف ؽذ٠ذ شذ٠ذ رغخ١ ؽراض

Iron + Oxygen —> Iron (III) oxide

3Fe(s) + 2O2(g) —> Fe3O4(s)

Lead, Pb

On strong heating, lead melts to a silvery ball. A powder is

gradually formed which is orange when hot and yellow when

cold.

ي ذرؽي ز اادج ا تدسج تشذما١ح ا ار ذرؽ. ػذ ارغخ١ اشذ٠ذ شصاص، ٠صش ٠رؽي ا وشاخ فع١ح

.تذسا ا ا االصفش ػذا ذثشد

Lead + Oxygen —> Lead (II) oxide

2Pb(s) + O2 (g) —> 2PbO(s)


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How do these examples demonstrate the changes in reactivity? For

example for some metals, the reaction is violent and the metals burns

like potassium. For other metals, the reactions are slow, like corrosion

of iron; however, Silver, gold and platinum do not react with oxygen in

the air. Refer to Figure 3.

ح غغح اشاغ١ح؟ فؼ عث١ اصاي ، ذرفاػ و١ف ذظش ز االصح ارغ١شاخ ف اصفاخ ؼاصش اى

تطئ ص ذفاػ ٠ى ثؼط اؼاصش ارفاػ تاغثح ت١ا. ذؽرشق تؼط اؼاصش تمج ص اثذاع١

.غ االوغع١ ف ااء ص ػاصش ازة افعح اثالذ١ػاصش أخش ال ذرفاػ ان اصذأ ،

Reacting Metals with Water: تفبعم انفهشاد يع انبء

Metals that react with water give off hydrogen gas and make the

water alkaline (basic) by producing metal hydroxides.

.٠ ، ذؽي ااء ا ل تاراض ١ذسوغ١ذ افضرى غاص ا١ذسض ذرفاػ افضاخ غ ااء

Metal + water metals hydroxide + Hydrogen (main

equation)

Potassium + water Potassium hydroxide + Hydrogen (example)

2 K + 2 H2O 2 KOH + H2

Sodium, Na

Potassium K

Calcium Ca

Zinc Zn

Iron Fe

Gold Au

Figure 3: Behavior of some metals while reacting with air.


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When a small piece of sodium is added to water, Hydrogen gas is given out in the

reaction. The resulting alkaline solution will turn red litmus blue because of the

sodium hydroxide formed.

ؽي ااذط سلح ػثاد ٠ؽي ا. لطؼح صغ١شج اصد٠ ا ااء، ٠رط غاص ا١ذسظ١ ارفاػػذ اظافح

.اشظ اؽشاء ا صسلاء ظد ١ذسوغ١ذ اصد٠

Sodium + water —> Sodium hydroxide solution + Hydrogen

4Na(s) + 4H2O (l) —> 4NaOH (aq) + 2H2 (g)

Magnesium, Mg

Magnesium virtually has no reaction with cold water. It reacts slowly with hot water to give hydrogen gas and white magnesium hydroxide, which is only slightly

soluble in water.

ت١ا ٠رفاػ تثطئ غ ااء اغاخ ١رط غاص ا١ذسظ١ ١ذسوغ١ذ .١ظ ان ذفاػ ظاش غ١غ١ غ ااء اثاسد

.تح ف ااءاغ١غ١ االت١ط از ٠زب تصؼ

Magnesium + water —> Magnesium hydroxide solution + Hydrogen

Mg(s) + 2H2O (l) —> Mg (OH) 2(s) + H2 (g)

Iron, Fe

Iron virtually has no reaction with cold water. Iron reacts with steam to give iron oxide and hydrogen gas.

.ن ذفاػ ظاش ؽذ٠ذ غ ااء اثاسد، ى ٠رفاػ غ تخاس ااء ١رط اوغ١ذ اؽذ٠ذ غاص ا١ذسظ١١ظ ا

Iron +H2O—> iron (III) oxide + Hydrogen

2Fe(s) + 3H2O (g) —> Fe (OH) 3 + 3H2 (g)

Lead, Pb

Lead virtually has no reaction with cold water or steam

.ان ذفاػ ظاش شصاص غ ااء اثاسد أ تخاس ااء١ظ


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Copper, Cu

Copper does not react with water.

.ال ٠رفاػ اؽاط غ ااء

Figure 4 Represents the woh elements reacts with water.

Reacting Metals with Dilute Acids:

Note: The reaction between iron and steam is reversible.

.ارفاػ ت١ اؽذ٠ذ اثخاس ذفاػ ػىغ: الؼظح

Tin, Lead, Copper, Silver, Gold and Platinum do not react with water or

steam.

.غ ااء أ تخاس ااء اثالذ١ امصذ٠ش ، اؽاط ، افعح، ازة ال ٠رفاػ

Test for Hydrogen Gas: انكشف ع انذرج

Hydrogen gas is recognized by the 'pop' sound when it burns. It is the sound

of a small explosion, Hydrogen is extremely flammable.

عتجز غبس انذرج طزع . ذ انفزقعخ صد افجبر ثظط .تش غبس انذرج ثبنشتعبل ثفزقعخ عذ تظخ

.االشتعبل

Figure 4: Behavior of metals reacting with water.

Lesson 5

http://www.gcsescience.com/irr.htm

http://www.gcsescience.com/o4.htm


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Reacting Metals with Dilute Acids:

:خففختفبعم انفهشاد يع االحبض انى

Metals react more vigorously with acids than with water. They make a

salt and hydrogen gas. If the salt produced is soluble in water, it gives

an alkali solution. See Figure 5. ز ارفاػالخ االالغ ٠رط. ذرفاػ افضاخ غ االؼاض اخففح تشذج أوصش ذفاػا غ ااء

. ارا وا اػ ارى رائة ف ااء ذرى ر١عح ز ارفاػالخ ؽا١ ل٠ح. غاص ا١ذسظ١ Metal + acid salt + Hydrogen (main equation)

Zinc + hydrochloric acid Zinc chloride + Hydrogen

(example )

Zn + 2HCl ZnCl2 + H2

Potassium reacts with dilute hydrochloric acid to give potassium chloride and

hydrogen gas.

.٠رفاػ اثذاع١ غ ؼط وس ااء اخفف ١رط وس٠ذ اثذاع١ غاص ا١ذسظ١

Potassium + dilute hydrochloric acid —> Potassium chloride + Hydrogen

2K(s) + 2HCl (aq) —> 2KCl (aq) + H2 (g)

Figure 5 Showing the test for H2.


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Sodium, Na

Sodium reacts with dilute hydrochloric acid to give sodium chloride and hydrogen

gas.

. غاص ا١ذسظ٠١رفاػ اصد٠ غ ؼط وس ااء اخفف ١رط وس٠ذ اصد

Sodium + dilute hydrochloric acid —> Sodium chloride + Hydrogen

2Na(s) + 2HCl (aq) —> 2NaCl (aq) + H2 (g)

Magnesium, Mg

Magnesium reacts with dilute hydrochloric acid to give magnesium chloride and

hydrogen gas.

.ع ؼط وس ااء اخفف ١رط وس٠ذاغ١غ١ غاص ا١ذسظ٠١رفاػ اغ١غ١

Magnesium + Hydrochloric acid —> Magnesium chloride + Hydrogen

Mg(s) + 2HCl (aq) —> MgCl2 (aq) + H2 (g)

Iron, Fe

Iron reacts with dilute hydrochloric acid to give iron chloride and hydrogen gas. .٠رفاػ اؽذ٠ذ غ ؼط وس ااء اخفف ١رط وس٠ذ اؽذ٠ذ غاص ا١ذسظ١

Iron + Hydrochloric acid —> Iron chloride + Hydrogen

Fe(s) + 2HCl (aq) —> FeCl2 (aq) + H2 (g)

Lead, Pb

Lead reacts very slowly with dilute hydrochloric acid to give lead chloride and

hydrogen gas.


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.٠رفاػ اشصاص تثطئ غ ؼط وس ااء اخفف ١رط وس٠ذاشصاص غاص ا١ذسظ١

Lead + Hydrochloric acid —> Lead chloride + Hydrogen

Pb(s) + 2HCl (aq) —> PbCl2 (aq) + H2 (g)

Figure 5: Behavior of elements while reacting with

acids.

Potassium


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1. What is meant by reactivity series?

أو النشاطية التفاعلية بسلسة المقصود هو ما

………………………………………………………………………………………………………………………

2. What is the reactivity series based on?

لترتيب العناصر الفلزات المختلفة؟ التفاعلية سلسة تعتمد ماذا على

………………………………………………………………………………………………………………………

3. How do metals react with water?

؟الماء مع الفلزات تتفاعل كيف

………………………………………………………………………………………………………………………

4. How do metals react with acids ?

؟االحماض مع الفلزات تتفاعل كيف

………………………………………………………………………………………………………………………


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5. How to test for hydrogen?

؟الهيدروجين غاز عن نكشف كيف

………………………………………………………………………………………………………………………

6. Fill the following table :المختبر بتقارير باالستعانة( كمجموعات) التالي الجدول أكمل

Mg

Cu

Al

Fe

Reaction

with oxygen

in the air

(O2)

Reaction

with water

(H2O)

Reaction

with acid

(HCl)


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7. Look at the Figure, in your own words explains what is meant by

reactivity series.

انظر الى الشكل المجاور ، عبر بكلماتك عن تعريف متسلسلة

ية أو التفاعليةالنشاط

………………………………………..………………………………

2- The most reactive metals are at the

……………….of the list and the least

reactive metals are at the …………..

3- They are based on their reactivity

with:

:تعتمد الفلزات على نشاطيتها في التفاعالت على

a-………………

b-………………

c- ………………

8. Complete the following:

:أكمل الفراغات التالية

1. When metals react with Oxygen they form………………….

2. When metals react with water they

produce………….………………………….and………………………..


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3. Metal + Water ...…………………… + ………….………..

4. Calcium + Oxygen ………………………. + ………………..….

5. Gold + water ………………………. + ………………..….

6. Iron + water ………………………. + ………………..….

7. Metals above hydrogen at the reactivity series will ………….. with

water.

.مع الماء......................... المعادن األعلى من الهيدروجين في السلسلة سوف .8

8. Metals below hydrogen at the reactivity series will …………….. with

water.

.مع الماء......................... المعادن اسفل من الهيدروجين في السلسلة سوف

9. When metals react with dilute acid they produce ………………….. and

………………..

.......................................................... ػذا ذرفاػ اؼاد غ األؼاض اخففح ذرط

10. Metal + dilute acid ……………………………. +………………….

11. Magnesium + Hydrochloric acid …………………………….

+………………….

Mg + HCl ……………..+…………………

12. Potassium + Hydrochloric acid

…………………………..+…………………

K + HCl ……………..+…………………


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13 .Copper + Hydrogen chloride

……………………………+…………………

9. Choose the right answer using the reactivity series:

: اختز االجبثخ انصححخ ثبالعتبد عه طهظهخ انتفبعهخ

a) Which one of these metals can react with dilute acids?

أ ذ انفهشاد تفبعم يع االحبض انخففخ

1. Gold. 2. Copper. 3. Iron. 4. Silver.


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Standards 13.7 Understand that reactive metals can displace less reactive ones


Objectives:

1. Understand that reactive metals can displace less reactive ones


Key Word

Displacement االحالل أ االساحخReaction

تفبعم


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Exploring Activity Displacing Metals:

In a test tube which is half full with Copper Sulphate

solution, place an iron in the solution for 5 min. Observe

what happens to the iron nail. ل تظغ غاس اؽذ٠ذ ف اثب اخرثاس رئ ؼر رصف ب ؽي وثش٠راخ

.اذشن االثب ذج ؼظ دلائك ش ل ترغع١ الؼظاذه. اؽاط

Making use of the reactivity series :طهخ انتفبعهخاطتخذايبد طم

In certain types of chemical reaction, one element replaces another

element in a compound. The reactivity series helps us to predict what

will happen in these reactions.

ف تؼط ارفاػالخ اى١١ائ١ح ٠ؽ أؼذ اؼاصش

ذىا عغح ارفاػ١ح . ىا االخش ف شوثاذ

.ف ذلغ ارا ع١ؽذز ف ارفاػالخ اى١١ائ١ح

The more reactive a metal, the

more it "likes" to exist as

compounds.

وا صادخ شاغ١ح افض، وا فعد اظد

.ػ شى شوثاخ

For example, iron is above

copper, which means it is more reactive than copper. So if these two

compete to be compounds, iron will win as you will see below. زه ارا ذافظ االشا ػ . فصال ٠ظذ اؽذ٠ذ أػ اؽاط ف اغغح ا ٠ؼ ا أوصش شاغا

. ذى٠ شوثاخ ٠فص اؽذ٠ذ

Lesson 6

Exploring activity

figure


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These types of reactions are called single displacement reactions or

(Displacement reactions) . .تعزف ذ انتفبعالد ثتفبعالد االحالل أ االساحخ االحبدخ

Competing for Oxygen: انتبفض نهتفبعم يع االكظج

In the reaction, the iron competes with copper and oxygen-and wins:

Iron + Copper oxide iron oxide + copper

Fe(s) + CuO(s) FeO(s) + Cu(s)

When a metal is heated with the oxide of a less reactive metal, it

takes the oxygen from it. .فظ ٠فص اؽذ٠ذ ػ اؽاط ٠رفاػ غ االوغع١ف ارفاػ ٠را

Mini Lab:

Metals in competition for oxygen- iron vs. copper.

Procedure:

1- Mix a spatula of iron filings and copper oxide

in a test- tube. Heat the mixture strongly,

Figure 1. . قى ثخهط يقذار يهعقخ ي ثزادح انحذذ اكظذ انحبص ف اجة اختجبر

.طخ انخهط ثقح

Analysis: ذؽ١ ارائط

1- Is there a reaction? Look for a red glow

spreading through the mixture. . ؼص ان ذفاػ و١١ائ؟ اتؽس ػ ادج ؼشاء ف اخ١ػ

2- After cooling the tube in a dish, is there pink

copper metal left? .و غؽق اؽاط اسد ال ترثش٠ذ اخ١ػ الؼع خ

Figure 1: After removing

the heat source, the

mixture keeps glowing

and iron oxide and

copper are formed.


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Other metals displace less reactive metals in the same way.

If the metal which is added is less reactive than the metal in the

compound then no reaction will occur. . و١١ائ ذفاػ أ ٠ؽذز ال اشوة ف اشذثػ فضاي شاغا ال اعاف افض وا إرا

Copper + Magnesium sulphate no reaction

metals displace less reactive metals from their oxides:

copper oxide + iron iron oxide + copper

.

Single Displacement Reaction: A metal will always displace a less reactive metal

from solutions of its compounds. شى ٠رى افض االوصش شاغا اؽي ؽ افض االل شاغا ف شوثاذ اظدج ػ: ذفاػالخ االصاؼح االؼاد٠ح

.ؽا١


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A-Use the reactivity series to complete the following equations:

انتبنخ األطئهخ ع نإلجبثخ انتفبعهخ طهظهخ اطتخذو

1. Magnesium + Zinc oxide ……….……… + ………………………….

2. Copper + Magnesium sulphate ……………… + ………………………

3. Iron + Silver chloride …………… +………………………………

4. Iron + Copper sulphate ………………………

Because iron is __________ reactive than copper.

5. Copper + Iron sulphate …………………………….

Because copper is ________ reactive than iron.

B- Complete the following:

1-The …………………. metal ………………….. the …………………. metal from its

compounds.

Documents

Grade 8 Unit M.2 - Metals Grade 8 Metals · Using ICT: Search the net for some videos ... Lesson Reacting Metals with Air (oxygen): ... Grade 8 Unit M.2 - Metals 10