Chemistry: 9. Acids and Bases
Syllabus
OC18 Use litmus or a universal indicator to test a variety of solutions, and classify these as acidic, basic or neutral
OC19 Investigate the pH of a variety of materials using the pH scale
OC20 Give examples of everyday acids and bases.
OC35 State the names and formulae of common strong acids and bases: H2SO4, HCl, NaOH, Ca(OH)2, and
understand that alkalis are soluble bases
OC36 Show the neutralisation of an acid with a base using an indicator
OC37 Understand that, when an acid reacts with a base, a salt and water are formed
i. HCl + NaOH → NaCl + H2O (word equation O.L.)
ii. 2HCl + CaCO3 → CaCl2 + CO2+ H2O (word equation O.L.)
OC38
Titrate HCl against NaOH, and prepare a sample of NaCl.
Student Notes
Both acids and bases are corrosive
Examples of everyday acids and bases
Acidic: citric acid, e.g. lemon juice, orange juice, apples, sour milk, vinegar, fizzy drinks and tea.
Neutral: pure water
Basic: tooth paste, lime water, bread soda, toothpaste, window cleaner and caustic soda.
Common strong acids and bases
Acids
hydrochloric acid
sulfuric acid
Bases
sodium hydroxide
calcium hydroxide
calcium carbonate
HCl
H2SO4
NaOH
Ca(OH)2
CaCO3
Alkalis are bases that are dissolved in water
Sodium hydroxide (caustic soda) is an example of an alkaline substance.
Indicators
An indicator is a compound which shows, by colour change, whether a substance is acidic or basic.
Litmus paper is an example of an indicator.
Experiment:
Use litmus or a universal indicator to test a variety of solutions, and classify these as acidic, basic or neutral
Equipment: Litmus paper / universal indicator and various household substances
Procedure: Drop a spot of universal indicator onto each substance and note the colour change.
Result:
Using litmus paper: acids turn litmus from blue to red, bases turn litmus from red to blue.
1
The pH scale
Litmus tells us if a substance is acidic or basic but not how acidic or
basic the substance actually is.
The pH scale allows to quantify (put a number) on the acid or base.
The pH of a solution can be found using:
(i) A pH meter
(ii) Universal indicator solution
(iii) pH paper (paper soaked in universal indicator solution)
The pH scale tells us how acidic or basic a solution is
pH greater than 7  the substance is alkaline
pH less than 7 the substance is acidic
pH 7  the substance is neutral
Experiment: To investigate the pH of a variety of materials
Apparatus: rack of test tubes
Chemicals: variety of substances – see ‘Examples of everyday acids and bases’ above
Procedure:
1. Put substances in test tubes (they must be dissolved in water if they are not a liquid).
2. Pour in a few drops of universal indicator and shake well (the colour will change according to how acidic or basic
the substance is).
3. Use the pH scale to write up results.
Universal Indicator pH Scale
Neutralisation
The properties of an acid are counteracted or neutralised by a base; this type of reaction is called a neutralisation
reaction.
When an acid reacts with a base the hydrogen in the acid is replaced by a metal and a salt is formed
Sodium and calcium are examples of metals
General formula to represent neutralisation reaction:
Acid
+
Base
→
Salt
Example 1
hydrochloric acid
HCL
+
+
sodium hydroxide
NaOH
→
→
sodium chloride
NaCl
Example 2
hydrochloric acid
2HCl
+
+
calcium carbonate
CaCO3
→
→
calcium chloride
CaCl2
2
+
+
+
Water
Water
H2O
+ CO2 + Water
+ CO2 + H2O
Titration
A titration is a method of analysis that will allow you to determine the precise endpoint of a reaction and therefore the
precise quantity of reactant in the titration flask.
A burette is used to deliver the second reactant to the flask and an indicator or pH Meter is used to detect the endpoint
of the reaction
To titrate hydrochloric acid (HCl) and sodium hydroxide (NaOH) and prepare a sample of sodium chloride
(NaCl)
Apparatus: A is a burette, B is a pipette, conical flask, retorts stand, , hotplate, white tile,
evaporating dish, dropper, beakers.
Chemicals: dilute hydrochloric acid, dilute sodium hydroxide, methyl orange indicator.
Method:
1. Set up apparatus as shown in diagram.
2. Using the pipette for accurate measurement, put 25cm3 of dilute sodium hydroxide
into the conical flask.
3. Fill the burette above the 0 mark with dilute hydrochloric acid.
4. Fill the part of the burette below the tap by letting some of the acid pour out (into an
empty beaker) until the level of the liquid is at the 0 mark.
5. Add around 3 drops of the indicator to the base in the conical flask.
6. Place the flask on a white tile under the burette.
7. Slowly add the acid into the conical flask until the liquid in the conical flask remains
pink.
8. The new reading on the burette is the amount of acid required to neutralise the base.
9. Pour the contents in the conical flask into the evaporating dish and evaporate it to
almost dryness.
10. Let solution cool - crystals of NaCl will form in the dish.
Result: White crystals of sodium chloride are formed.
Extra Stuff
Hydrochloric acid is very corrosive but can be found in our stomach because it aids digestion.
Everyday examples of neutralisation
1. A bee sting (acid) neutralised with baking soda (base)
2. A wasp sting (base) can be neutralised by vinegar (acid)
3. Toothpaste neutralises the acid on your teeth that is produced from bacteria.
4. Antacid neutralises excess acid in the stomach.
5. Lime is used to reduce acidity in soil.
Salt formed from neutralisation
The first part of the base name (Na in NaOH) becomes the first part of the salt.
The second part of the acid name (Cl in HCL) becomes the second part of the salt name.
The name of the salt depends on the acid you start with:
Hydrochloric acid → chlorides
Nitric acid → nitrates
Sulfuric acid → sulfates
Titration - extra
Slowly add the acid into the conical flask while swirling the flask with your other hand.
When you start to see a pink colour appear where the acid drips, add the acid one drop at a time until the liquid in the
conical flask remains pink.
Wash out apparatus and repeat experiment without using the indicator.
Use the measurement from the new reading to get the exact amount needed to neutralise the base.
3
1.
Exam Questions
[2006 OL] [2008 OL]
Many substances found in the home are acids or bases.
Acid
Complete the table below identifying one acid and one
base from the list on the right.
Base
Vinegar
Water
Oven Cleaner
2. [2007]
Name an everyday substance with a
pH of less than 7.
3. [2008]
The diagram shows the positions of
some common substances on the pH
scale.
Classify the substances shown as
acidic, basic or neutral.
4. [2007 OL][2007]
Describe, with the help of a labelled diagram, how you could investigate simple household substances to see if
they were acidic, basic or neutral.
Use the following headings: Equipment and chemicals, Procedure, Result, Labelled diagram
5. [2009 OL]
The diagram shows the apparatus
set up by a student to investigate
the pH of three different liquids A,
B and C.
A few drops of universal indicator
were added to each liquid in a test
tube.
Study the diagram and the results
given. Then answer the questions
below.
(i) Which test tube, A, B or C, contained distilled water? __________
(ii) Which test tube, A, B or C, contained an acid? ________________
Give a reason for your answer.
6. [2006 OL] [2008 OL]
When hydrochloric acid reacts with sodium hydroxide to neutralise each other, a salt and water are
formed. Some of the pieces of equipment used in this experiment are shown in the diagram.
(i) Name the piece of equipment labelled A.
(ii) Name the salt formed when sodium hydroxide is neutralised by hydrochloric acid?
(iii) Which piece of equipment A or B is usually used to measure the hydrochloric acid during this
experiment?
(iv) How can you tell by using an indicator that enough hydrochloric acid has been added to neutralise
the sodium hydroxide?
7. [2006]
The pieces of laboratory equipment shown, together with some other items, were used to
prepare a sample of sodium chloride.
(i) Name item A or item B
(ii) There were 25 cm3 volumes of base used in this experiment.
Describe how the piece of equipment A was used to measure the volume of acid required
to neutralise this amount of base.
(iii) Name a suitable acid and name a suitable base for the preparation of sodium chloride by
this method.
(iv) Write a chemical equation for the reaction between the acid and the base that you have
named.
4
8. [2009]
(i) What is item A used for in the titration of an acid with a base?
(ii) What happens when an acid reacts with a base?
9. [2007]
Give the formula of a common base.
10. [2007]
Alkalis are water-soluble bases. Name a substance, which is alkaline.
11. [2008 OL]
The diagram shows a piece of magnesium being burned in air.
Magnesium oxide is formed.
When magnesium oxide is tested with moist red litmus indicator it changes
colour to blue. What does this tell us about magnesium oxide?
Other Test Questions
1. Complete the chemical equation for the reaction between the acid and base below:
HCl + NaOH
+
2. Give the formula for the base calcium hydroxide.
3. Name an acid and a base commonly found in the school lab.
4. (i) Name the item of glassware with graduations down the side that is used in a titration to dispense a known
volume of liquid.
(ii) Describe how you would accurately read the level of the liquid dispensed from this item of glassware:
5. (i) Name two chemicals that are used to prepare a sample of sodium chloride.
(ii) What is the function of the indicator used in the experiment to prepare a sample of sodium chloride.
6. State the approximate pH of hydrochloric acid.
7. State the approximate pH of sodium hydroxide solution.
8. What term is used to describe the reaction when a strong acid is mixed with a strong base.
9. (i) Name an indicator.
(ii) What colour will this indicator be in hydrochloric acid?
10. Given a diagram of a pipette and burette
11.
12.
13.
14.
15.
Name the pieces of glassware used to prepare a sample of sodium chloride by titration
An indicator is used to determine the end point of the titration. Name a suitable indicator.
How would you know the endpoint had been reached?
What colour change was observed in the conical flask?
What conclusion can you make from the colour change observed:
16. How could you collect the NaCl from the solution in the conical flask?
17. Complete and balance the following equation:
+ NaOH
NaCl +
18. What is a neutralization reaction?
5
Chemistry: 10. Air and Oxygen
Syllabus
OC21 Understand that air is a mixture of gases, and state the composition of air (approximately 78% N2 and 21% O2,
with CO2, water vapour and other gases making up the balance)
OC22 Show that approximately one fifth of the air is oxygen; show that there is CO2 and water vapour in air
OC23 Demonstrate and describe what happens when (i) a wooden splint and (ii) a piece of magnesium are burned in
air
OC24 Prepare a sample of oxygen by decomposing H2O2 using MnO2 as a catalyst (word equation and chemical
equation)
OC25 Investigate the ability of oxygen to support combustion in a wooden splint and a candle, and state two uses of
oxygen
OC26 Burn carbon and magnesium in oxygen, and test the products using moist litmus paper
OC53 Recall that fossil fuels are sources of hydrocarbons, and that they produce CO2 and H2O when burned
OC54 List two examples of fossil fuels
OC55 Describe the role of the combustion of fuels and of SO2 in the production of acid rain, and describe the effects
of acid rain
OC56 Describe the effect of acid rain on limestone and on plants
OC57 Understand that natural gas is mainly methane
Student Notes
Composition of the air
The atmosphere is made up of 78% nitrogen and 21% oxygen
Carbon dioxide, water vapour and various other gases make up the remainder.
To show that approximately one fifth of the air is oxygen
Method one
Set up as shown - the water rises approximately one fifth of the height
of the graduated cylinder to replace the oxygen used up by the burning
candle.
Method two
Volume of air before heating = 100cm3
Volume of air after heating the copper = 79cm3
Volume of oxygen present in 100cm3 = 21 cm3
Percentage of air = 21/100 = 21%
To show that there is carbon dioxide in air
When air is drawn through limewater by a vacuum pump the limewater turns milky proving there is carbon dioxide in
air.
To show that there is water vapour in air
Fill a test-tube with ice and water and leave it for a few minutes; a liquid will form on the outside of the test-tube.
Test the liquid using blue cobalt chloride paper – it turns pink showing that the liquid was water which condensed.
Preparation of oxygen
6
Hydrogen peroxide

oxygen
+
water
H2O2

O2
+
H2O
Manganese dioxide (MnO2) is added in as a catalyst (to speed up the reaction)
Procedure
1. In this case hydrogen peroxide (labelled X in the diagram) is added to
manganese dioxide (labelled Y in the diagram).
2. Oxygen then bubbles through the water in the trough.
3. Test its pH using universal indicator paper.
Conclusion: oxygen is a colourless, odourless gas. It has a pH of 7 so it is a
neutral
To investigate the ability of oxygen to support combustion in a wooden splint and a candle
Oxygen will relight a glowing splint. This is the characteristic test for oxygen.
Uses of oxygen
1. Used in welding to increase combustion
2. Used in medicine to help breathing
Burning carbon in oxygen
Heat a piece of carbon over a Bunsen burner and put it into a jar of oxygen.
Result: The carbon ignites.
Conclusion: oxygen aids combustion.
Testing the products
Add water and test using blue litmus paper.
It turns red showing that carbon dioxide is an acidic gas.
Burning magnesium in oxygen
Hold a piece of magnesium ribbon over a Bunsen burner until it ignites.
Result: The magnesium burns with a bright flame.
Testing the products
Add water and test using red litmus paper.
It turns blue showing that magnesium oxide is a base.
In general metal oxides tend to be basic and non-metal oxides are acidic
7
Fossil fuels
A fuel is a substance that burns in oxygen to produce heat
Fossil fuels are fuels that were formed from the remains of plants and animals that lived millions of years ago
Although the three types of fossil fuels (coal, oil and gas) look different, they all contain the same sort of chemicals
called hydrocarbons.
Hydrocarbons are compounds that contain hydrogen and carbon only.
Fossil fuels are sources of hydrocarbons and produce CO2 and H2O when burned
Examples of fossil fuels
Peat, coal, oil, natural gas
Natural gas is mainly methane (CH4)
Acid Rain
The role of the combustion of fuels and of sulphur dioxide in the production of acid rain
Many fossil fuels contain small amounts of sulphur.
As the fuel gets burnt the sulphur combines with oxygen to from sulphur dioxide (SO2) which gets released into the air
When this gas dissolves in water (e.g. rainwater) it forms sulphuric acid, which is corrosive.
This is the main culprit in acid rain.
Acid Rain is rain water with a pH of less than 5.5
The effect of acid rain on limestone and on plants
Acid rain destroys lakes, kills fish and harms trees.
It corrodes limestone and iron.
Ways to reduce effects of acid rain
1. Install chemical plants to remove sulfur dioxide from emissions in the chimney of power stations.
2. Reduce the content of sulfur in fuels like oil and gas. However, this makes them more expensive.
3. Install catalyst converts in cars to remove harmful oxides of nitrogen from exhaust fumes.
4. Burn less fossil fuels and use other types of energy such as wind energy, hydroelectric energy, etc.
8
Exam Questions
1. [2008 OL][2009 OL]
Name any three gases normally found in clean air.
2. [2006]
The composition of air can be investigated in different ways.
Two experiments are shown in the diagram.
In Experiment A the air was pushed repeatedly over the heated copper powder and only 79 cm3 of gas remained at
the end of the experiment.
(i) Why is it necessary to let the apparatus cool down before measuring the volume of the remaining gas?
(ii) Why did the volume of gas decrease and then remain steady?
(iii) What is the remaining gas mainly composed of?
(iv) Experiment B is less accurate than Experiment A.
Give a reason why this is so.
3. [2006 OL]
(i) What happens when a “glowing splint” (very hot piece of wood) is placed in a gas jar of oxygen?
(ii) Give one property of oxygen that this demonstrates.
4. [2008 OL]
The diagram shows a piece of magnesium being burned in air.
Magnesium oxide is formed.
When magnesium oxide is tested with moist red litmus indicator it
colour to blue.
What does this tell us about magnesium oxide?
5. [2008]
Magnesium was burned in oxygen as shown in the diagram.
(i) What colour was the flame?
(ii) Pieces of moist blue and red litmus paper were mixed with the product of the combustion.
What result was seen?
(iii) What conclusion can be made from the result of the litmus test?
6. [2006]
In 1774 Joseph Priestley, an English chemist, discovered oxygen.
(i) Name the two chemicals that you reacted together to prepare oxygen in the school
laboratory.
(ii) One of the chemicals acted as a catalyst.
Which one of the two chemicals used was the catalyst?
7. [2009]
Oxygen can be prepared by decomposing liquid A using solid B as
a catalyst.
This preparation is shown in the diagram.
(i) Name liquid A.
(ii) Name solid B.
(iii) What is a catalyst?
9
changes
8. [2006 OL]
Oxygen gas can be prepared in a school laboratory using the apparatus drawn on
the right.
(i) Identify a liquid X and a solid Y that can be used in this preparation.
(ii) Solid Y speeds up the breakdown of liquid X. What name is given to this type of
chemical?
Fossil fuels and acid rain
9. [2007 OL]
Fossil fuels are sources of hydrocarbons.
(i) Name one element found in all hydrocarbons.
(ii) The burning of fossil fuels can give rise to acid rain.
Give one harmful effect of acid rain.
(iii) Natural gas is mainly composed of one particular hydrocarbon.
What is the name of this gas?
10. [2006 OL]
(i) Natural gas is mainly methane (CH4).
Name one of the two elements found in methane.
(ii) Name one gas produced when methane is burned in air.
11. [2008 OL]
(i) Choose two fossil fuels from the list on the right.
(ii) Name two products formed when a fossil fuel is burned in air.
12. [2009 OL]
(i) Write the letter F beside the name of a fossil fuel in the table.
(ii) Write the letter P beside a product formed when a fossil fuel is burned.
13. [2008]
(i) Natural gas is a fossil fuel. What is a fossil fuel?
(ii) Name the main constituent of natural gas.
14. [2006]
(i) Fossil fuels are burnt to provide energy to generate
electricity.
Give the name or formula of a compound of sulfur
formed when a sulphur containing fossil fuel burns
in air.
(ii) Acid rain is formed when this sulfur compound
dissolves in and reacts with water in the
atmosphere.
Describe the effect of acid rain on limestone.
15. [2009]
The photograph shows the emissions from a coal burning electricity generating station.
Name a pollutant present in the emissions and describe its effect on the environment.
16. [2006]
In Ireland 90% of electricity is generated by burning fossil fuels compared to other European
countries who have an average of 50% use of fossil fuels and a 30% use of fossil fuels in the
USA.
List two disadvantages, excluding acid rain, of this heavy reliance on fossil fuels for the
production of electricity.
10
Coal
Nuclear
Oil
Tidal
Coal
Nuclear
Oxygen
Water
Other Test Questions
1. What are the four main components of air?
2. What is the approximate percentage of oxygen in air?
3. What is the approximate of nitrogen in air?
4. How would you demonstrate the percentage of air in oxygen?
5. How would you test for carbon dioxide in air?
6. How would you test for water vapour in air?
7. How would you demonstrate what happens when a wooden splint is burned in air?
8. How would you demonstrate what happens when a piece of magnesium is burned in air?
9. Draw a labelled diagram of the apparatus used to prepare oxygen gas in the school laboratory.
10. (i) Given the diagram of apparatus used to prepare oxygen
(ii) Name the liquid and the solid required to produce oxygen in the lab.
(iii) What is the purpose of the solid?
(iv) What are such substances called?
11. Describe using a labelled diagram, how a sample of oxygen could be prepared and collected.
12. Describe a laboratory experiment to prepare a sample of oxygen by decomposing H2O2 using MnO2 as a catalyst.
13. Give the word equation for this reaction.
14. Give the chemical equation for this reaction.
15. Describe how you would investigate the ability of oxygen to support combustion in a wooden splint and a candle.
16. Give two uses of oxygen.
17. How would you test for the products of burning carbon and magnesium in oxygen, using moist litmus paper.
18. A sample of carbon (charcoal) was burnt in oxygen.
(i) What colour was the carbon?
(ii) What result was achieved when the compound formed was tested with universal indicator paper?
(iii) What conclusion can be made about the compound from the result achieved?
19. A sample of carbon(charcoal) was burnt in oxygen.
The compound formed was tested using blue litmus paper and a colour change was observed.
(i) What was the colour change?
(ii) What is the name of the compound formed?
20. Complete the word equation showing the products formed when a hydrocarbon is burned in oxygen:
Hydrocarbon + oxygen
+
21. What type of fire extinguisher would be suitable for a chip pan fire?
22. What type of fire extinguisher would be suitable for burning fabric or cloth?
23. What are the three conditions are necessary for a fire.
24. What is a catalyst?
11
25. Three gas jars contain oxygen, hydrogen and carbon dioxide gas.
(i) How would you identify which one contains oxygen gas?
(ii) How would you identify which one contains hydrogen gas?
(iii) How would you identify which one contains carbon dioxide gas?
(iv) Which of these gases could be used in fire extinguishers?
26. In an experiment to determine the composition of air, 100cm3 air was pushed repeatedly over heated copper
powder from one syringe to another. At the end, only 79cm3 was left.
(i) Why is it necessary to let the apparatus cool down before measuring the volume of the remaining gas?
(ii) Why did the volume of gas decrease and then remain steady?
(iii) What is the remaining gas mostly composed of?
(iv) A second experiment can be performed to show the composition of air using a burning candle placed inside an
inverted graduated cylinder placed in a basin of water. This is a less accurate method. Why?
27. (i) Balance the chemical equation for the decomposition of hydrogen peroxide
H2O2
H2O
+
O2
(ii) Name the catalyst used in this experiment.
(iii) Describe a laboratory test for oxygen gas.
28. When iron is exposed to both water and oxygen, it rusts.
(i) Draw a diagram to show what would happen when you place steel wool in a test tube and invert it in a basin
of water.
(ii) What can be concluded from this experiment?
Fossil fuels and acid rain
1. Give one example of a fossil fuel.
2. Write down one harmful effect of acid rain.
3. Identify one gas that causes acid rain.
4. State one way in which acid rain damages the environment.
5. Name one of the gases released when fossil fuels are burnt.
Describe a harmful effect of this gas.
6. Name a gas that dissolves in rain water to form acid rain
7. Give the name or formula of a compound of sulphur formed when a fossil fuel containing sulphur is burned.
8. What can we do to prevent acid rain?
9.
(i)
(ii)
(iii)
(iv)
(v)
What are hydrocarbons?
When hydrocarbons are burnt, water vapour is produced. How do we confirm the presence of water vapour.
Identify the black deposit formed on surfaces above the combustion of a hydrocarbon.
What other gas is formed during the combustion of a hydrocarbon?
How do we test for the presence of this gas?
12
Chemistry: 11. Carbon Dioxide
Syllabus
OC27 Prepare carbon dioxide (word equation and chemical equation), and show that it does not support combustion
OC28 Carry out simple tests on carbon dioxide involving its reaction with limewater (word equation and chemical
equation), and with moist litmus paper
OC29 Investigate the density of carbon dioxide relative to air (qualitative only), and state two uses of carbon dioxide
Student Notes
Preparation of carbon dioxide
Calcium carbonate + Hydrochloric acid
(Marble chips)
CaCO3
+
2HCl

Calcium Chloride
→
CaCl2
+ Water +
+
H2O
Carbon Dioxide
+
CO2
Procedure
Set up as shown (calcium carbonate is the chemical name for marble chips).
1. Slowly release the hydrochloric acid into the flask underneath.
2. Carbon dioxide is collected it the gas jar
Test 1:
Pour a small volume of limewater into the jar and shake – the limewater will turn
milky showing that the gas is carbon dioxide.
Test 2:
Add water to a fresh jar of carbon dioxide and test with blue litmus paper: it turns
red demonstrating that it is an acid.
Limewater and carbon dioxide
Limewater
Ca(OH)2
+
+
→
carbon dioxide
→
CO2
calcium carbonate
CaCO3
To show that carbon dioxide does not support combustion
Light a wooden splint and insert it into a gas jar of carbon dioxide.
Result: the splint will extinguish showing that carbon dioxide does not support combustion.
Carbon dioxide has a greater density than air
Demonstration
Pour the gas over the candle as shown.
Because carbon dioxide is denser than air the gas sinks and extinguishes the candle.
Uses of carbon dioxide
1. Fizzy drinks
2. Fire extinguishers
3. Special effects on stage (dry ice in water cause a ‘smoke’ effect)
13
+
+
water
H2O
Exam Questions
1. [2007]
Give the chemical name for marble.
2. [2009 OL] [2007 OL]
The diagram shows an arrangement of apparatus suitable for the preparation of carbon dioxide
gas in a school laboratory.
Name suitable substances X and Y from which carbon dioxide can be made.
3. [2007]
(i) The diagram shows an apparatus that can be used for the preparation and collection of
carbon dioxide.
Give the formula of a suitable acid.
(ii) What physical property of carbon dioxide allows the gas to be collected in the manner
shown in the diagram?
4. [2006 OL]
Name the chemical that turns milky white if carbon dioxide is bubbled through it.
5. [2008]
The liquid and solid shown in the diagram react together to produce a gas that turns
limewater milky. Name a liquid and a solid that react together in this way.
6. [2006]
Carbon dioxide turns limewater milky.
Complete the chemical equation for the reaction of carbon dioxide with limewater.
Ca(OH)2 + CO2 →
7. [2007]
If a strip of moist blue litmus paper and a strip of moist red litmus paper are put
into a jar of carbon dioxide what effect, if any, does the gas have on them?
8. [2009]
Carbon was burned in oxygen and the products tested with pieces of moist red and blue litmus paper.
Give the result of the litmus test described above and make a conclusion based on this result.
9. [2006 OL]
The diagram shows a gas jar of carbon dioxide gas being poured onto a lighting candle.
(i) What happens to the lighting candle when the carbon dioxide gas is poured over it?
(ii) What does this tell us about carbon dioxide gas?
10. [2007 OL]
The diagram shows a gas jar of carbon dioxide gas being poured onto a lighting candle.
The candle quenches (goes out). This test demonstrates two properties of carbon dioxide
gas.
State these two properties.
11. [2007][2009]
Give two uses of carbon dioxide.
14
Other Test Questions
1.
(i) Describe a laboratory experiment to prepare carbon dioxide
(ii) Give the word equation for this reaction.
(iii) Give the chemical equation for this reaction.
2. How would you demonstrate that carbon dioxide does not support combustion?
3.
(i) Describe how you would carry out a simple test to demonstrate the reaction between carbon dioxide and
limewater.
(ii) Give the word equation for this reaction.
(iii) Give the chemical equation for this reaction.
4. Describe how you would carry out a simple test to demonstrate the reaction between carbon and moist litmus
paper.
5. Describe how you would investigate the density of carbon dioxide relative to air.
6. Give two uses of carbon dioxide.
7. Give the formula for limewater.
8. Identify the milky-white precipitate formed from the reaction between limewater and carbon dioxide.
9. Give two uses of carbon dioxide.
10. Name a suitable liquid and solid that could be used for the preparation of carbon dioxide.
11. Write the chemical reaction for the laboratory preparation of carbon dioxide.
12. Give a test for carbon dioxide gas
13. Complete and balance the following chemical equation for the reaction between limewater and carbon dioxide:
Ca(OH)2 + CO2
+
14. Complete and balance the following equation:
HCl + CaCO3
+
15
+