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Grade 8 Unit M.2 - Metals
1
Grade 8
Metals
Iron Ore, where we extract iron from!
Molten Metal
Mining for Copper
Aluminum!
Rusting!
Grade 8 Unit M.2 - Metals
2
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.
Grade 8 Unit M.2 - Metals
3
KEY WORDS
Reactivity series
انتفبعهخ طهظخ
Acid حط
Base قبعذ
Electrolysis انكزثبئ انتحهم
Reactive يتفبعم أ شط
Dilute يخفف
Alkali قه
Grade 8 Unit M.2 - Metals
4
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
Grade 8 Unit M.2 - Metals
5
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
Grade 8 Unit M.2 - Metals
6
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)
Grade 8 Unit M.2 - Metals
7
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.
Grade 8 Unit M.2 - Metals
8
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
Grade 8 Unit M.2 - Metals
9
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
Grade 8 Unit M.2 - Metals
10
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.
Grade 8 Unit M.2 - Metals
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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.
Grade 8 Unit M.2 - Metals
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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
Grade 8 Unit M.2 - Metals
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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
………………………………………………………………………………………………………………………
Grade 8 Unit M.2 - Metals
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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)
Grade 8 Unit M.2 - Metals
15
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………………………..
Grade 8 Unit M.2 - Metals
16
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 ……………..+…………………
Grade 8 Unit M.2 - Metals
17
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.
Grade 8 Unit M.2 - Metals
18
Standards 13.7 Understand that reactive metals can displace less reactive ones
from their compounds.
Objectives:
1. Understand that reactive metals can displace less reactive ones
from their compounds.
Key Word
Displacement االحالل أ االساحخReaction
تفبعم
Grade 8 Unit M.2 - Metals
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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
Grade 8 Unit M.2 - Metals
20
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.
Grade 8 Unit M.2 - Metals
21
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
Grade 8 Unit M.2 - Metals
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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.