The Periodic TableCambridge IGCSE Chemistry: Topic test

20 questions, 54 marks

Cambridge IGCSE Chemistry

The Periodic Table topic test

Total 54 marks

Name

Class

Date

1
A chemistry teacher gives students the electronic configuration of an unknown element, W: 2,8,3, and asks them to use only this information to predict its position and properties in the Periodic Table.
(a)
In which group and period of the Periodic Table would element W be found?
[1 mark]
AGroup III, Period 3
BGroup III, Period 2
CGroup VIII (0), Period 3
DGroup II, Period 3
(b)
Based on its position, would element W be expected to have properties more similar to a metal or to a non-metal, and why?
[1 mark]
AMore non-metallic, because it is in Group III, which is entirely made up of non-metals
BMore metallic, because elements towards the left of a period tend to be metallic and element W is likely to lose its 3 outer electrons to form a 3+ ion
CNeither metallic nor non-metallic, because Group III elements are always noble gases
DMore metallic, because it has 8 electrons in its second shell, giving it a full outer shell
(c)
State the number of electrons in the outer shell of element W, and explain how you determined the group number from the electronic configuration 2,8,3.
[2 marks]
Total for question 1: 4 marks
2
A student is shown a small, sealed glass ampoule containing a tiny sample of caesium, a Group I metal below potassium, which chemists never handle directly because of its extreme reactivity with air and water.
(a)
Based on the trend in reactivity down Group I, how would caesium be expected to react with water compared with potassium?
[1 mark]
ALess vigorously, because reactivity decreases down Group I
BAbout the same, because all Group I metals react identically with water
CMore vigorously, because reactivity increases down Group I
DCaesium would not react with water at all, unlike potassium
(b)
Based on the trend down Group I, how would the melting point of caesium be expected to compare with the melting point of potassium?
[1 mark]
AHigher, because melting point increases down Group I
BThe same, because melting point does not change within a group
CImpossible to predict from trends within a group
DLower, because melting point decreases down Group I
(c)
Explain, in terms of atomic structure, why reactivity increases down Group I.
[2 marks]
Total for question 2: 4 marks
3
A company manufacturing water-purification tablets for hikers tests two chemicals: chlorine-releasing tablets and iodine-releasing tablets. In a school investigation modelling this, a student first adds a few drops of chlorine water (pale yellow-green) to a colourless solution of potassium iodide, and a brown colour develops. In a second test tube, she adds iodine solution (brown) to a colourless solution of potassium chloride, and there is no colour change.
(a)
Explain, in terms of reactivity, why chlorine water added to potassium iodide solution produces a colour change (forming iodine), but iodine solution added to potassium chloride solution produces no reaction.
[3 marks]
(b)
Write the balanced symbol equation for the reaction between chlorine and potassium iodide solution, and use the idea of relative reactivity within Group VII to explain why this makes chlorine, rather than iodine, the more effective disinfectant chemical for the purification tablets.
[4 marks]
Total for question 3: 7 marks
4
A glassmaker adds small amounts of different transition element compounds to molten glass to colour stained glass windows. Iron(II) compounds produce pale green glass, while iron(III) compounds produce yellow-brown glass; copper(II) compounds produce blue-green glass.
(a)
Using the properties of transition elements, explain why compounds of iron and copper are able to produce a range of different colours in the glass, referring to the idea of variable oxidation numbers, and explain how the presence of iron(II) rather than iron(III) compounds could be identified without directly viewing the finished glass.
[6 marks]
(b)
Transition elements, including iron and copper, are also widely used as catalysts in industrial processes, unlike Group I metals. Explain, in terms of general properties of transition elements compared with Group I metals, why transition elements rather than Group I metals are generally chosen as catalysts and as structural/decorative metals.
[6 marks]
Total for question 4: 12 marks
5
An engineer designs a weather balloon and chooses to fill it with helium gas rather than hydrogen gas, even though hydrogen is less dense and would allow the balloon to lift a slightly greater load.
(a)
Why is helium chosen instead of hydrogen for this balloon, despite hydrogen being less dense?
[1 mark]
AHelium is a noble gas and is chemically unreactive, so it will not catch fire like hydrogen
BHelium is much cheaper to produce than hydrogen
CHelium reacts with oxygen in the air to form a stable, non-flammable compound
DHelium has a stronger, more rigid outer electron shell than hydrogen, making it heavier
(b)
Which statement correctly explains, in terms of electronic configuration, why helium (and the other noble gases) is so unreactive?
[1 mark]
ANoble gas atoms have no electrons in their outer shell at all
BNoble gas atoms have a full outer electron shell, so they do not readily gain, lose or share electrons
CNoble gas atoms have only one electron in their outer shell, like Group I metals
DNoble gas atoms lose electrons very easily to form stable positive ions
(c)
State two physical properties, other than being unreactive, that make the noble gases as a group suitable for filling balloons and airships.
[2 marks]
Total for question 5: 4 marks
6
A student is told that an unknown element, Q, has 15 protons in its nucleus and therefore an electronic configuration of 2,8,5.
(a)
Which group and period of the Periodic Table would element Q be found in?
[1 mark]
AGroup III, Period 2
BGroup V, Period 2
CGroup V, Period 3
DGroup VIII (0), Period 3
(b)
Based on its position, how many electrons would you predict element Q gains or loses when it forms an ion, and what charge would the ion have?
[1 mark]
AQ loses 5 electrons to form a 5+ ion
BQ gains 5 electrons to form a 5- ion
CQ loses 3 electrons to form a 3+ ion
DQ gains 3 electrons to form a 3- ion, completing a full outer shell of 8
(c)
Explain how the number of electrons in the outer shell of an element relates to the group number of the Periodic Table it is found in.
[2 marks]
Total for question 6: 4 marks
7
A student adds a few drops of orange bromine water to a colourless solution of potassium chloride, and observes no colour change even after several minutes. She then adds a few drops of the same bromine water to a colourless solution of potassium iodide, and the solution turns brown.
(a)
Explain, in terms of reactivity, why bromine produces a colour change with potassium iodide solution but not with potassium chloride solution.
[3 marks]
(b)
Write the balanced symbol equation for the reaction between bromine and potassium iodide solution, and predict, giving a reason, whether fluorine would be expected to react with potassium chloride solution.
[4 marks]
Total for question 7: 7 marks
8
A teacher demonstrates the reaction between sodium (Group I) and chlorine gas (Group VII), which burns vigorously to form white sodium chloride. The class is then asked to predict what would happen if potassium reacted with chlorine, and separately if sodium reacted with bromine, instead.
(a)
Using trends in reactivity within Group I and within Group VII, predict and explain whether the reaction between potassium and chlorine would be more or less vigorous than the reaction between sodium and chlorine.
[6 marks]
(b)
Using trends in reactivity within Group VII, predict and explain whether the reaction between sodium and bromine would be more or less vigorous than the reaction between sodium and chlorine, and state the type of bonding and the formula of the salt that would form.
[6 marks]
Total for question 8: 12 marks

End of questions