ChemistryClass No.: _____
Chapter 12Reactivity of metals
12.1How to compare the reactivity of metals?
What are the criteria of putting metal in the order of reactivity?
1)2)
3)
Experiment 12.1To arrange five metals in order of reactivity. (Refer to the laboratory worksheet.)
12.2Comparing reactivity of metals
A)Reaction with oxygen (air) (Table 12.1 P. 254)
i)Appearance
Most of metals are ______in colour. Metals are ready to react with ______in air (to tarnish) to form an ______layer on metal surface. A ______surface is shown when metal is ______cut or scratched.
Reactive metals, such as sodium and potassium are stored under ______.
ii)Heating the metals in air
Some reactive metals burn vigorously with a characteristic coloured flame when heated.
Metal / Colour of flamePotassium, K
Sodium, Na
Calcium, Ca
Magnesium, Mg
iii)Products of the reaction
1)Metals react with ______in air to form ______.
Metal + oxygen ______
e.g., ___Mg(s) + ______
ChemistryClass No.: _____
Chapter 12Reactivity of metals
2)Oxides of transition metals are usually ______.
e.g., CuO, ZnO, & Fe3O4 .
3)______metals such as silver, ______and ______have ______reaction with oxygen.
Arrange the metals in the descending (decreasing) order of reactivity:
______
______
B)Reaction with water
i)Reaction with cold water
______metals such as ______, ______and ______react vigorously to form ______and ______.
Metal + water ______
e.g., __Na(s) + __ H2O(l) ______
Ca(s) + __H2O(l) ______
ii)Reaction with hot steam
Less reactive metals have ______reaction with cold water. But, they react readily with hot steam to form ______and ______. (e.g., ______, ______& ______)
Draw the experimental set-up for the reaction between steam and magnesium:
Metal + steam ______
e.g., Mg(s) + H2O(g) ______
Zn(s) + H2O(g) ______
Fe(s) + H2O(g) ______
ChemistryClass No.: _____
Chapter 12Reactivity of metals
iii)Is there any reaction between aluminium and steam? Briefly explain.
______
______
______
iv)Summary Table : Refer to figure 12.11 P. 257
C)Reaction with dilute acids
Dilute acids: dilute ______acid & ______acid (except dilute nitric acid)
Metals that are ______reactive than ______, reacts with dilute acids giving (liberating) ______gas.
Metal + hydrochloric acid ______+ ______
Metal + sulphuric acid ______+ ______
e.g., Reaction with magnesium with dilute hydrochloric acid
Equation: ______
e.g., Reaction with zinc with dilute sulphuric acid
Equation: ______
NB.1)Test for hydrogen, H2(g)
______
______
2)Never add sodium or potassium into dilute acids. Why?
______
______
______
3)The reactions of dilutesulphuric acid with calcium or lead stop after a short time. Why?
______
______
______
ChemistryClass No.: _____
Chapter 12Reactivity of metals
D)Summary of the reactions Book 1 P. 257 & P. 258
12.3Chemical Equations
A + B C + D
(reactants) (products)
Formulae of the reactants are written on the ______hand side of the arrow and the formulae of the products are written on the ______hand side of the arrow.
‘ + ‘ on the left hand side of the arrow means ‘______’.
‘ ‘ means ______.
ChemistryClass No.: _____
Chapter 12Reactivity of metals
a)Useful information from a balanced equation:
i)the ______involved.
ii)the ______formed.
iii)the ______of the substances involved.
iv)the ______of each substance involved.
b)Rules for writing balanced chemical equations
i)Determining the types of reactants involved and the products formed in the reaction.
ii)Write down the correct formulae of reactants on the ______hand side of the arrow.
iii)Write down the correct formulae of products on the ______hand side of the arrow.
iv)Balance the equation with simple whole numbers such that the total number of each type of atoms are equal on both sides of the arrow.
v)Put in the physical states for each substance.
(s) : solid state
(l) : liquid state
(g) : gas state
(aq) : aqueous solution
Examples:
1)Reaction of magnesium with dilute hydrochloric acid
______
2)Reaction of potassium with cold water
______
3)Reaction of aluminium with hot steam
______
4)Reaction of zinc with dilute hydrochloric acid
______
ChemistryClass No.: _____
Chapter 12Reactivity of metals
12.4Why metals have different reactivity?
Atoms tend to get (attain) inert gas structure either by ______or ______electrons in chemical reactions.
e.g.,Sodium (its electronic structure) : ______
Sodium reacts by ______electron.
Half equation: ______
e.g., Chlorine (its electronic structure): ______
Chlorine reacts by ______electron to form ______ion.
Half equation: ______
The relative reactivity of metals depends on the ______of losing electrons. Their ease of losing electrons is related to their ______of outermost shell electrons and their ______of electronic shells.
e.g., For the third period, the decreasing order of reactivity of metals is:
______
Reason: ______
______
______
For the Group 1 metals, the decreasing order of reactivity of metals is:
______
Reason: The attractive force between the nucleus and the outermost shell electron decrease with increasing atomic size. Thus, ______
______
______
NB. The relative reactivity of other metals (i.e., below aluminium in the reactivity series) cannot be explained in Form 5 level.
ChemistryClass No.: _____
Chapter 12Reactivity of metals
12.5Application of the reactivity series
a)Extraction of metals (Mineral ores: refer to Chapter 11 P. 233)
Getting a metal from its ore is called ______the metal.
Compounds that are found in metal ore are ______, ______, ______and ______.
Only ______metals such as ______and ______are found free (as elements) in nature.
Different methods of extraction:
1)______
2)______
3)______
i)Heating the ore alone.
Only fit (work) for metals that are at the ______of the reactivity series (i.e., unreactive metals).
e.g., 1)Heating silver(I) oxide
______
silver(I) oxide silver oxygen
(brown solid) grey silvery solid
2)Heating mercury(II) oxide
______
mercury(II) oxide mercury oxygen
red powder silvery mirror
3)Heating mercury(II) sulphide in air
Mercury(II) sulphide reacts with oxygen in air to form mercury and sulphur dioxide.
______
N.B.How does the stability of compounds relate to the reactivity of metals? Why?
______
ChemistryClass No.: _____
Chapter 12Reactivity of metals
ii)Heating metal oxide with carbon / charcoal / coke. (Reduction with carbon)
What is reduction?
______.
Heat metal oxides (such as copper(II) oxide or lead(II) oxide) in a charcoal block (with coke).
What do you see when lead(II) oxide is heated with carbon?
______
______
Write a balanced equation for the reaction involved.
______
What is the role of carbon in the above reaction?
______
N.B.At Bunsen flame (up to 1200oC), carbon can ______lead(II) oxide and those oxides of metals that are below lead in the reactivity series.
In industry, with higher temperature (1500o C) carbon can reduce up to ______oxide. Refer to Table 12.3 P.233
Write an equation for the reduction of copper(II) oxide by coke.
______
(black solid)(brown metal)
N.B.What is oxidation?
______
ChemistryClass No.: _____
Chapter 12Reactivity of metals
Sometimes, the ore is not a metal oxide. Briefly explain how to extract lead from lead(II) sulphide.
______
______
______
iii)Electrolysis of molten compounds of reactive metals
Reactive metals such as ______, ______, ______, ______and ______cannot be extracted from their ores by heating with carbon. They are extracted from molten metal compounds by ______.
Electrolysis is an expensive method.
e.g., Aluminium – from the electrolysis of hot ______. P. 236
Refer to the table 11.2 (P. 237). How did the year of discovery of metals relate to the relative reactivity of the metals? Briefly explain.
______
______
______
b)Reduction with metals
What is the role of metal in the oxidation-reduction reaction?
______
Suggest a metal that can be used to extract copper by heating it with copper(II) oxide.
______
Briefly explain your choice.
______
______
______
Write a balanced equation for the reduction of copper(II) oxide.
______
Can copper reduce magnesium oxide to magnesium? Why?
______
______
N.B.Thermit reaction – for welding railway lines.
By igniting a solid mixture of aluminium powder and iron(III) oxide.
Equation: ______
ChemistryClass No.: _____
c)Metal displacement reaction
i)Adding copper to silver nitrate solution
What do you observe when a piece of copper is added into silver nitrate solution? ______
______
______
Why is there a reaction?
______
______
Write a balanced equation for the reaction.
______
The ______ion does not take part in the reaction. It is the ______ion, and can be deleted from the full equation.
Ionic equation for the reaction:
______
ii)Adding zinc to copper(II) sulphate solution
What do you observe when a piece of zinc is added into copper(II) sulphate solution? ______
______
______
Why is there a reaction?
______
______
Write a balanced equation for the reaction.
______
Ionic equation: ______
iii)Adding copper to magnesium sulphate solution
What do you observe when a piece of copper is added into magnesium sulphate solution? ______
______Why ? ______
______
ChemistryClass No.: _____
12.6Ionic Equations
Ionic equation is an equation, which is written with ions that have taken part in the chemical reaction.
Example: Reaction of magnesium with dilute hydrochloric acid.
Dilute hydrochloric acid contains hydrogen ions (H+(aq)) and chloride ions (Cl-(aq)).
Magnesium chloride solution contains magnesium ions (Mg2+(aq)) and chloride ions (Cl-(aq)).
The ______ions do not take part in the reaction. They remain unchanged before and after the reaction. The chloride ions are called ______ions and can be deleted from the equation.
Ionic equation: ______
Rules for writing ionic equations:
i)Determining the types of reactants involved and the products formed in the reaction.
ii)Write down the correct formulae of reactants on the ______hand side of the arrow.
iii)Write down the correct formulae of products on the ______hand side of the arrow.
iv)Balance the equation with simple whole numbers such that the total number of each type of atoms is equal on both sides of the arrow.
v)Decide which substances exist as mobile ions in solution. Write down the ions of these substances. (Do not change the formulae of solids and gases.)
vi)Delete the ions not taking part in the reaction.
Ex.1)Neutralisation (Reaction of dilute hydrochloric acid with sodium hydroxide)
Full equation: ______
Ionic equation: ______
2)Reaction of calcium carbonate with dilute hydrochloric acid
Full equation: CaCO3(s) + 2HCl(aq) CaCl2(aq) + CO2(g) + H2O(l)
Ionic equation: ______
3)Metal displacement reaction (Reaction of zinc and silver nitrate solution)
Full equation : Zn(s) + 2AgNO3(aq) 2Ag(s) + Zn(NO3)2(aq)
Ionic equation: ______
4)Heating a mixture of ammonium chloride solution and potassium hydroxide solution
Full equation: NH4Cl(aq) + KOH(aq) KCl(aq) + NH3(g) + H2O(l)
Ionic equation: ______
Chemistry Worksheets / HKCWCC / Chapter 12P 1