1. Acids, Bases and Salts LEARNING OUTCOMES Chapter 10
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
LEARNING OUTCOMES
Define acid and acid anhydride
Investigate the reactions of non-oxidising acids with metals, carbonates, hydrogen carbonates and bases
Define base and alkali
Investigate the reaction of bases with ammonium salts
Relate acidity and alkalinity to the pH scale
Discuss the strength of acids and alkalis on the basis of their completeness of ionisation
Define acidic, basic, amphoteric and neutral oxides
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2. Acids, Bases and Salts LEARNING OUTCOMES Chapter 10 Define salt
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
LEARNING OUTCOMES
Define salt
Identify an appropriate method of salt preparation based on the solubility of the salt
Distinguish between acidic and normal salts
Investigate neutralisation reactions using indicators and temperature changes
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3. Acids, Bases and Salts What are acids? Chapter 10
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Chapter 10
Acids, Bases and Salts
What are acids?
Fruits like apples, oranges and pineapples taste sour because they contain acids.
Acids also turn blue litmus paper red.
Acids produce hydrogen ions H+ in water.
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4. Acids, Bases and Salts Definition of An Acid Chapter 10
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Chapter 10
Acids, Bases and Salts
Definition of An Acid
An acid is a substance which produces hydrogen ions, H+(aq) in water.
For example, hydrochloric acid dissolves in water to form hydrogen ions and chloride ions:
HCl(aq)  H+(aq) + Cl-(aq)
It is the hydrogen ions which turn blue litmus to red and give acids their characteristic properties.
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5. Acids, Bases and Salts What are acids?
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
What are acids?
pop
Other chemical properties of acids
Acids react with metals to produce hydrogen gas. E.g. Mg + H2SO4  MgSO4 + H2
( test for hydrogen gas)
Acids react with carbonates to produce carbon dioxide. E.g. CaCO3 +2HCl  CaCl2 + H2O + CO2
Limewater turns chalky
HCl+CaCO3
(test for carbon dioxide)
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6. Acids, Bases and Salts What are acids?
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
What are acids?
Other chemical properties of acids
Acids react with bases to form a salt and water only.
E.g. sulphuric acid reacts with copper(II) oxide to form a salt called copper(II) sulphate and water: H2SO4 + CuO  CuSO4 + H2O
This reaction is called neutralisation.
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7. Acids, Bases and Salts A Strong Acid
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Chapter 10
Acids, Bases and Salts
A Strong Acid
Strong acid
A strong acid is an acid that is completely ionised in water. This means that all the acid molecules become ions in the water.
Examples of strong acids are: sulphuric acid, hydrochloric acid and nitric acid.
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8. Acids, Bases and Salts A Weak Acid
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Chapter 10
Acids, Bases and Salts
A Weak Acid
Weak acid
A weak acid is an acid that is only partially ionised in water. This means that only a few molecules of the acid become ions in water.
E.g.s. of weak acids are: ethanoic acid, citric acid and carbonic acid.
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9. Acids, Bases and Salts Some Common Acids Name of acid Formula
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Some Common Acids
Name of acid
Formula
Sulphuric acid
H2SO4
Hydrochloric acid
HCl
Nitric acid
HNO3
Citric acid
C6H8O7
Ethanoic acid (vinegar)
CH3COOH
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10. Acids, Bases and Salts Uses of Acids
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Uses of Acids
Hydrochloric acid is used in the industry to remove rust from metals before they are painted.
Sulphuric acid is used to make fertilisers and detergents.
Ethanoic acid is used in vinegar for cooking and to preserve food such as vegetables.
Citric acid is used in making fruit salts.
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11. Acids, Bases and Salts Quick check 1
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Quick check 1
What ions do acids produce in water?
State three properties of acids.
Explain what is meant by a strong acid. Give one example of a strong acid.
Explain what is meant by a weak acid. Give one example of a weak acid.
Some dry citric acid crystals are placed on a dry piece of litmus paper. Will there be a colour change? Explain your answer.
Solution
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12. Solution to Quick check 1
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Solution to Quick check 1
Hydrogen ions
(a) Acids have a sour taste. (b) Acids turn blue litmus to red. (c) Acids react with metals to produce hydrogen.
A strong acid is an acid that is completely ionised in water. E.g. sulphuric acid.
A weak acid is an acid that is only partially ionised in water. E.g. ethanoic acid.
There will be no colour change because there is no water, so the citric acid cannot form hydrogen ions.
Return
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13. Acids, Bases and Salts Bases
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Bases
A base is an oxide or hydroxide of a metal.
Examples of bases are: sodium oxide, sodium hydroxide, copper(II) oxide, copper(II) hydroxide, etc.
A base reacts with an acid to form a salt and water only. E.g. CuO + H2SO4  CuSO4 + H2O
This process is called neutralisation.
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14. Acids, Bases and Salts Alkalis
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Chapter 10
Acids, Bases and Salts
Alkalis
If a base is soluble in water, it is called an alkali.
An alkali is a soluble base which produces hydroxide ions, OH− (aq) in water.
Sodium hydroxide is an alkali because it dissolves in water to produce hydroxide ions: NaOH(aq)  Na+(aq) + OH−(aq)
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15. Difference between base and alkali
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Chapter 10
Acids, Bases and Salts
Difference between base and alkali
Copper(II) hydroxide is a base but not an alkali. This is because it is insoluble in water and hence cannot produce hydroxide ions in water.
Is this true?
All alkalis are bases, but not all bases are alkalis.
BASE
ALKALI
CuO
Cu(OH)2
NaOH
NH3(aq)
KOH
Fe2O3
Ca(OH)2
MgO
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16. Acids, Bases and Salts Chemical properties of alkalis
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Chemical properties of alkalis
Alkalis have a bitter taste and soapy feel.
Alkalis turns red litmus to blue.
Alkalis react with acids to from salt and water only. E.g. 1. NaOH + HCl  NaCl + H2O
E.g KOH + H2SO4  K2SO H2O
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17. Acids, Bases and Salts Chemical properties of alkalis
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Chemical properties of alkalis
Alkalis react with ammonium salts to produce ammonia gas.
Ammonia gas is acidic, thus it turns red litmus paper blue.
Ammonia gas is very soluble in water and gives out a pungent smell. E.g.1: NaOH + NH4Cl  NaCl + NH3 + H2O
NH3 gas produced turns red litmus blue
Sodium hydroxide + ammonium chloride
E.g. 2: Ca(OH)2 + 2NH4Cl  CaCl2 + 2NH3 + 2H2O
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18. Acids, Bases and Salts Uses of Bases
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Uses of Bases
Sodium hydroxide and potassium hydroxide are used in making soaps.
Ammonia solution is used in window cleaners.
Magnesium hydroxide is used in toothpastes to neutralise the acid produced by bacteria.
Calcium hydroxide (slaked lime) is used to neutralise acids found in acidic soil.
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19. Acids, Bases and Salts Some Common Alkalis Chapter 10 Name
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Some Common Alkalis
Name
Chemical formula
Sodium hydroxide
NaOH
Potassium hydroxide
KOH
Calcium hydroxide
Ca(OH)2
Ammonia solution (ammonium hydroxide)
NH3(aq)
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20. Acids, Bases and Salts Quick check 2
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Quick check 2
What is a base? Give 3 examples of bases.
Define what is an alkali. Give 3 examples of alkalis.
State 3 properties of alkalis.
Explain why iron(II) hydroxide is a base, but not an alkali.
Write balanced chemical equations for the following reactions: (a) potassium hydroxide + ammonium chloride (b) calcium hydroxide + ammonium chloride
Solution
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21. Solution to Quick check 2
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Solution to Quick check 2
A base is an oxide or hydroxide of a metal. E.g. sodium oxide, copper(II) oxide, calcium hydroxide.
An alkali is a soluble base which produces hydroxide ions in water. E.g. sodium hydroxide, potassium hydroxide, calcium hydroxide.
(i) Alkalis turn red litmus blue. (ii) Alkalis react with acids to produce a salt and water. (iii) Alkalis react with ammonium salts to produce ammonia.
Iron(II) hydroxide is a base, but not an alkali because it is insoluble in water, so it cannot produce hydroxide ions in water.
(a) KOH + NH4Cl  KCl + H2O + NH3 (b) Ca(OH)2 + 2NH4Cl  CaCl H2O + 2NH3
Return
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22. Acids, Bases and Salts Indicators
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Indicators
Indicators are substances which show different colours in acidic and alkaline solutions.
Litmus is a common indicator. It is red in acidic solutions and blue in alkaline solutions.
Other important indicators are shown in the table on the next slide.
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23. Acids, Bases and Salts Indicators Chapter 10 Indicator
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Indicators
Indicator
Colour in strong Acids
pH at which colour changes
Colour in strong alkalis
Methyl orange
red
pH 4
yellow
Litmus
pH 7
blue
Phenolphthalein
colourless
pH 9
pink
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24. Acids, Bases and Salts The pH Scale
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
The pH Scale
The pH of a solution tells us how acidic or alkaline a solution is.
The pH is a measurement of the hydrogen ion concentration in a solution.
The pH scale ranges from 0 to 14.
The pH of a solution can be measured with a pH meter.
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25. Acids, Bases and Salts The pH Scale
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
The pH Scale
The lower the pH, the more acidic the solution is.
The higher the pH, the more alkaline the solution is.
pH 7 is neutral.
Distilled water, sugar solution and most salt solutions are neutral (pH 7).
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26. The Universal Indicator
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
The Universal Indicator
The Universal Indicator consists of a mixture of dyes which changes its colour in different pH solutions.
We can use the Universal Indicator to tell us the approximate pH of a solution.
The Universal Indicator or pH paper changes its colour according to the pH shown in the chart below.
Box of pH paper with colour chart
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27. Acids, Bases and Salts Types of Oxides Chapter 10
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Types of Oxides
Elements burn or react with oxygen to form oxides.
There are 4 types of oxides: acidic oxides, basic oxides, amphoteric oxides and neutral oxides.
An acidic oxide is an oxide of a non-metal. It dissolves in water to form an acid. Acidic oxides react with alkalis to form salts .
A basic oxide is an oxide of a metal. If soluble, it will dissolve in water to form an alkali. Basic oxides react with acids to form salts.
An amphoteric oxide is an oxide which can react with both acids and alkalis to form salts.
A neutral oxide does not react with either acids or alkalis.
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28. Acids, Bases and Salts Types of Oxides Chapter 10 Acidic Oxides
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Types of Oxides
Acidic Oxides
Basic Oxides
Amphoteric Oxides
CO2 , SO2 NO2 , NO
Na2O, CaO, K2O, MgO, CuO
Al2O3 , PbO , ZnO
React with alkalis to form salts
React with acids to form salts
React with both acids & alkalis to form salts
Neutral Oxides
H2O, CO , N2O
Do not react with both acids & alkalis
4 TYPES OF OXIDES
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29. Acids, Bases and Salts Quick check 3
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Quick check 3
Name 3 common indicators and their colour change in strong acidic and strong alkaline solutions.
What is meant by the pH of a solution? What is the pH of : (a) hydrochloric acid, (b) citric acid, (c) sodium chloride solution, (d) sodium hydroxide solution?
What are the 4 types of oxides? Give one example of each type of oxide.
What colours would you expect to see when the following indicators are added to a solution of pH 5? (a) litmus, (b) phenolphthalein, (c) methyl orange
Solution
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30. Solution to Quick check 3
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Solution to Quick check 3
Litmus: red, blue; Phenolphthalein: colourless, pink; Universal Indicator: red, violet
The pH of a solution measures the acidity or alkalinity of a solution. (a) 0 – 1, (b) 3 – 4, (c) 7, (d) 13 – 14.
Acidic oxides, basic oxides, amphoteric oxides and neutral oxides. E.g. sulphur dioxide, sodium oxide, aluminium oxide, water.
(a) litmus: red, (b) phenolphthalein: colourless, (c) methyl orange: yellow
Return
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31. Acids, Bases and Salts Salts +
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Salts
A salt is formed when an acid is neutralised by a base.
A salt contains two parts:
Metal part : cation (comes from the base)
Non-metal part : anion (comes from the acid) +
Acid
Base
Salt
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32. Acids, Bases and Salts Examples of Salts Chapter 10 Table 1
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Examples of Salts
Table 1
Base (alkali)
Acid
Salt formed
Sodium hydroxide
Hydrochloric acid
Sodium chloride
Potassium hydroxide
Potassium chloride
Sulphuric acid
Sodium sulphate
Potassium sulphate
Calcium hydroxide
Nitric acid
Calcium nitrate
Ammonia solution
Ammonium nitrate
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33. Acids, Bases and Salts Uses of Salts
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Uses of Salts
Sodium chloride is used as table salt and to preserve meat and vegetables.
Sodium chloride is electrolysed to obtain sodium and chlorine in the industry.
Ammonium nitrate and ammonium sulphate are used as plant fertilisers.
Magnesium sulphate, commonly called Epsom salt, is used as a bath-salt.
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34. Methods of Preparing Salts
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Chapter 10
Acids, Bases and Salts
Methods of Preparing Salts
1. Action of acid on alkali
ACID + ALKALI  SALT + WATER
This process is called neutralisation.
To carry out the neutralisation of the acid and alkali exactly, a method called titration is used.
The salts listed in Table 1 can be prepared by the titration method.
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35. To prepare sodium nitrate by neutralisation (titration method)
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
To prepare sodium nitrate by neutralisation (titration method)
burette
Pipette
Sodium nitrate and water (phenolphthalein as indicator)
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36. To prepare sodium nitrate by neutralisation (titration method)
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
To prepare sodium nitrate by neutralisation (titration method)
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37. Acids, Bases and Salts Methods of Preparing Salts
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Methods of Preparing Salts
2. Action of acid on insoluble base
ACID + BASE  SALT + WATER
This method is used for bases which are insoluble in water.
Examples of salts prepared by this method: * copper(II) sulphate from copper(II) oxide and sulphuric acid: CuO + H2SO4  CuSO4 + H2O
* zinc chloride from zinc oxide and hydrochloric acid: ZnO + 2HCl  ZnCl2 + H2O
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38. Preparation of copper(II) sulphate (acid on insoluble base)
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Preparation of copper(II) sulphate (acid on insoluble base)
Step 1 Place about 50 cm³ of dilute sulphuric acid in a beaker and gently warm the acid. Copper(II) oxide is added, a little at a time, to the acid, until no more can dissolve.
Equation: CuO + H2SO4  CuSO4 + H2O
Step 2 Filter off the excess copper(II) oxide using a filter paper and funnel. Collect the filtrate which contains copper(II) sulphate in an evaporating dish.
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39. Preparation of copper(II) sulphate (acid on insoluble base)
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Preparation of copper(II) sulphate (acid on insoluble base)
Step 3 Evaporate the copper(II) sulphate solution until it is saturated. Allow the hot solution to cool to form crystals.
Step 4 Filter off the copper(II) sulphate crystals formed and dry them by pressing them between sheets of filter paper.
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40. Acids, Bases and Salts Methods of Preparing Salts
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Methods of Preparing Salts
3. Action of acid on a carbonate
ACID + CARBONATE  SALT + WATER + CO2
Eg.1 Sulphuric acid on sodium carbonate
H2SO Na2CO3  Na2SO4 + H2O + CO2
Eg Hydrochloric acid on calcium carbonate
2HCl + CaCO3  CaCl2 + H2O + CO2
This method is similar to the previous method; instead of the oxide, the carbonate is added in excess to the acid.
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41. Acids, Bases and Salts Methods of Preparing Salts
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Methods of Preparing Salts
4. Action of acid on a metal
ACID + METAL  SALT + HYDROGEN
Eg Sulphuric acid on zinc
H2SO Zn  ZnSO4 + H2
Eg Hydrochloric acid on magnesium
2HCl + Mg  MgCl2 + H2
NOTE: Only metals like magnesium, zinc and iron are suitable. Metals like sodium, potassium and calcium are explosive with acids; while metals like lead and copper are unreactive with acids.
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42. Making zinc sulphate (acid on metal)
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Making zinc sulphate (acid on metal)
Can you describe how zinc sulphate is prepared with the aid of the diagrams?
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43. Acids, Bases and Salts Methods of Preparing Salts + Chapter 10
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Methods of Preparing Salts
5. Double Displacement (Precipitation method)
This method is used to prepare insoluble salts.
Two solutions are mixed together to produce a precipitate of
the insoluble salt which can then be filtered off from the mixture. +
CB (aq)
AD (s)
AB (aq)
CD (aq)
E.g. Lead(II) nitrate Sodium chloride  Lead(II) chloride + Sodium nitrate Pb(NO3)2(aq) NaCl(aq)  PbCl2(s) NaNO3(aq)
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44. Other salts made by precipitation method
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Other salts made by precipitation method
Silver chloride
AgNO3(aq) + HCl(aq)  AgCl(s) + HNO3(aq)
Barium sulphate
Ba(NO3)2(aq) + H2SO4(aq)  BaSO4(s) + 2HNO3(aq)
Copper(II) carbonate CuSO4(aq) + Na2CO3(aq)  CuCO3(s) + Na2SO4(aq)
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45. Table of soluble and insoluble salts
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Table of soluble and insoluble salts
This table will be useful to you when preparing salts
Soluble salts
Insoluble salts
All sodium, potassium and ammonium salts
All carbonates except those of sodium, potassium and ammonium
All nitrates
None
All sulphates except those of calcium, lead and barium
Calcium sulphate, lead(II) sulphate and barium sulphate
All chlorides except those of silver and lead
Silver chloride and lead(II) chloride
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46. Acids, Bases and Salts Quick check 4 Chapter 10
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Quick check 4
1. Define what is salt. Give an example of a soluble and insoluble salt.
2. State 4 methods of making salts.
3. State whether the following salts are soluble or insoluble:
(a) sodium carbonate, (b) calcium chloride, (c) barium sulphate, (d) lead(II) nitrate, (e) lead(II) chloride.
4. State the method you would choose to prepare the following salts: (a) potassium nitrate, (b) zinc nitrate, (c) magnesium sulphate, (d) copper(II) carbonate. For each method, state the chemicals you will need and
write a balanced chemical equation for the reaction.
Solution
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47. Solution to Quick check 4
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Solution to Quick check 4
A salt is formed when an acid is neutralised by a base. E.g. soluble salt: sodium chloride E.g. insoluble salt: calcium sulphate
(a) Acid on metal, (b) acid on base, (c) acid on carbonate, (d) precipitation method
Soluble: sodium carbonate, calcium chloride, lead(II) nitrate; Insoluble: lead(II) chloride, barium sulphate
(a) potassium nitrate: titration method; potassium hydroxide and nitric acid; KOH + HNO3  KNO3 + H2O (b) zinc nitrate: acid on carbonate; nitric acid and zinc carbonate; HNO3 + ZnCO3  Zn(NO3)2 + H2O + CO2 (c) magnesium sulphate: acid on metal; magnesium and sulphuric acid; Mg + H2SO4  MgSO4 + H2 (d) copper(II) carbonate: precipitation method; copper(II) sulphate and sodium carbonate; CuSO4(aq) + Na2CO3(aq)  CuCO3(s) + Na2SO4(aq)
Return
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48. State symbols in equations
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
State symbols in equations
The state symbols in a chemical equation tell us about the state of each reactant and product.
The following are the state symbols used:
Solid  (s)
Liquid  (l)
Gas  (g)
Aqueous solution  (aq)
Example: CaCO3(s) + 2HCl(aq)  CaCl2(aq) + H2O(l) + CO2(g)
The above equation tells us that solid calcium carbonate reacts with a solution of hydrochloric acid to produce liquid water and carbon dioxide gas.
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49. Writing ionic equations
Chemistry Expression
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Chapter 10
Acids, Bases and Salts
Writing ionic equations
Ionic equations are general equations which can apply to any particular reaction.
They represent ions taking part in a reaction, leaving out those ions which do not react (spectator ions).
They contain state symbols.
Only solutions (aq) can form ions; gases, solids and liquids do not ionise.
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50. Acids, Bases and Salts Writing ionic equations Chapter 10
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Chapter 10
Acids, Bases and Salts
Writing ionic equations
Steps in writing ionic equations
EXAMPLE 1
HCl (aq) + NaOH (aq)  NaCl (aq) + H2O (l)
Step 1: Break substances with (aq) into its ions: H+(aq) + Cl-(aq) + Na+ (aq) + OH-(aq)  Na+ (aq) + Cl- (aq) + H2O (l)
Step 2: Remove similar ions from both sides of equation.
Step 3: Rewrite the equation with the final ions left: H+ (aq) OH- (aq)  H2O(l)
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51. Acids, Bases and Salts Writing ionic equations Chapter 10
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Writing ionic equations
Steps in writing ionic equations
EXAMPLE 2
2HCl(aq) + CaCO3 (s)  CaCl2 (aq) + H2O (l) + CO2 (g)
Step 1: Break those with (aq) into its ions: 2H+ (aq) + 2Cl-(aq) + CaCO3 (s)  Ca2+ (aq) + 2Cl- (aq) + H2O (l) + CO2 (g)
Step 2: Remove similar ions on both sides.
Step 3: Rewrite the equation with the ions left: H+(aq) + CaCO3(s)  Ca2+(aq) + H2O(l) + CO2(g)
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52. Acids, Bases and Salts Writing ionic equations Chapter 10
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Writing ionic equations
Steps in writing ionic equations
EXAMPLE 3
Pb(NO3)2(aq) + 2NaCl (aq)  PbCl2 (s) + 2NaNO3 (aq)
Step 1: Break those with (aq) into its ions: Pb2+(aq) + 2NO3-(aq) + 2Na+(aq) + 2Cl- (aq)  PbCl2(s) + 2Na+(aq) + 2NO3- (aq)
Step 2: Remove similar ions on both sides.
Step 3: Rewrite the equation with the ions left: Pb2+(aq) + 2Cl- (aq)  PbCl2(s)
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53. Acids, Bases and Salts Quick check 5
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Quick check 5
Construct (i) a balanced chemical equation and (ii) an ionic equation for each of the following reactions: (1) Sulphuric acid + potassium hydroxide (2) Nitric acid + sodium hydroxide
(3) Silver nitrate solution + sodium chloride solution
(4) Calcium carbonate + hydrochloric acid
(5) Magnesium + hydrochloric acid
Solution
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54. Solution to Quick check 5
Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
Solution to Quick check 5
H2SO4(aq) + 2KOH(aq)  K2SO4(aq) + 2H2O(l) H+(aq) + OH-(aq)  H2O(l)
HNO3(aq) + NaOH(aq)  NaNO3(aq) + H2O(l) H+(aq) + OH-(aq)  H2O(l)
AgNO3(aq) + NaCl(aq)  AgCl(s) + NaNO3(aq) Ag+(aq) + Cl-(aq)  AgCl(s)
CaCO3(s) + 2HCl(aq)  CaCl2(aq) + H2O(l) + CO2(g) CaCO3(s) + 2H+(aq)  Ca2+(aq) + H2O(l) + CO2(g)
Mg(s) + 2HCl(aq)  MgCl2(aq) + H2(g) Mg(s) + 2H+(aq)  Mg2+(aq) + H2(g)
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55. Chemistry Expression
2019/5/29
Chapter 10
Acids, Bases and Salts
To learn more about Acids, Bases and Salts, click on the links below!
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