Chemistry 9701 · AS & A Level
The Periodic Table: chemical periodicity
100 practice questions on The Periodic Table: chemical periodicity, with worked solutions and instant marking.
The consecutive elements X, Y and Z are all in Period 3 of the Periodic Table. Of these three elements, Y has the greatest first ionisation energy and the smallest melting point. What are the identities of X, Y and Z?
Feb/March 2016
When a spillage of metallic sodium is being dealt with, it is important that no toxic or flammable products are produced. Which material should be used if metallic sodium is spilled?
Feb/March 2016
For the element sulfur, between which two ionisation energies is the difference greatest?
Feb/March 2016
This question concerns Period 3 elements and the compounds they form.
Feb/March 2016
The values of property X for five elements from the third period of the Periodic Table, P, Q, R, S and T, are shown. P, Q, R, S and T have consecutive atomic numbers. The letters do not stand for the symbols of the elements. Which row correctly identifies property X and element R?
Feb/March 2017
The table gives information about some of the elements in period 3.
Feb/March 2017
Which oxide does not dissolve in aqueous sodium hydroxide?
Feb/March 2018
X, Y and Z are three elements in the third period. When X is reacted with chlorine, a liquid product is formed. When Y reacts with chlorine, a solid product is formed; this dissolves in water to make a solution of pH $7$. When Z reacts with chlorine, a solid product is formed; this dissolves in water to make a solution of pH $6$. Which of these elements conduct electricity well?
Feb/March 2018
An atom has the electronic configuration of its two outermost shells as $3s^2 3p^6 3d^5 4s^2$. Which atom is this?
Feb/March 2018
The sketch graph plots the first ionisation energies for six consecutive elements in the Periodic Table. The letters do not represent the elements' symbols.
Feb/March 2018
A solid Period 3 element, Q, is allowed to react with oxygen gas, producing compound R. If R is then added to water, the pH falls. What might the empirical formula of R be?
Feb/March 2019
Carbon and nitrogen lie next to each other in the Periodic Table. Which properties do they both share?
Feb/March 2020
Which row is the correct one?
Feb/March 2021
In the Periodic Table, where would you place the element whose outer electron shell arrangement is $4s^2 4p^3$?
Feb/March 2021
The first ionisation energy of potassium, $\mathrm{K}$, is $418\,\text{kJ mol}^{-1}$. The first ionisation energy of strontium, $\mathrm{Sr}$, is $548\,\text{kJ mol}^{-1}$. Which statement assists in explaining why $\mathrm{Sr}$ has a higher first ionisation energy than $\mathrm{K}$?
Feb/March 2022
A student carried out an investigation on the chloride of a Period 3 element. The student recorded the following observations. "The substance was a white, crystalline solid. It dissolved readily in water to form a solution with pH $12$. When it was put into a test-tube and warmed in a roaring Bunsen flame, the substance only melted after several minutes of heating." What can be inferred from this record?
Feb/March 2022
The elements in Period 3 and the compounds they form display patterns across the period from sodium to chlorine. Which row is correct?
Feb/March 2022
Fig. 1.1 illustrates the way first ionisation energies change across Period 2.
Feb/March 2022
The Period 3 oxides listed are: $\text{Na}_2\text{O}$, $\text{Al}_2\text{O}_3$, $\text{P}_4\text{O}_6$, $\text{P}_4\text{O}_{10}$, $\text{SO}_2$, $\text{SO}_3$.
Feb/March 2022
Which statement correctly describes the first ionisation energies of magnesium and neon?
Feb/March 2023
Two Period 3 elements, X and Y, each react separately with oxygen to produce solid oxides. The oxide of X does not dissolve in water. The oxide of Y dissolves in water, giving a solution that can dissolve the oxide of X. What could X and Y be?
Feb/March 2023
V and Z are both Period 3 elements in the Periodic Table. Each one forms a single stable ion that contains no other element. The atomic radius of each element and the ionic radius of the ion mentioned above are shown. Which statement is true?
Feb/March 2023
The Pauling electronegativity values of elements may be used to forecast the chemical behaviour of compounds. Use the data in Table 1.1 to answer the questions that follow.
Feb/March 2023
The relative size of property $X$ for five elements is shown below. $P$, $Q$, $R$, $S$ and $T$ are all in Period 3 and have successive atomic numbers. The letters do not represent the real chemical symbols of the elements. Which row gives the correct answer for property $X$ and element $R$?
Feb/March 2024
Element $X$ belongs to Period 3. Element $X$ reacts with oxygen to form a solid, $Y$. If solid $Y$ is placed in water, it gives a solution with a pH of less than $7$. Which element is $X$?
Feb/March 2024
This question is about isolated gaseous species. The species $\text{F}^-$, Ne and $\text{Na}^+$ are isoelectronic. This indicates that they contain the same number of electrons. In what sequence do their radii increase?
Feb/March 2024
Q, R and S are adjacent elements in Period $3$ of the Periodic Table. Element R has the greatest first ionisation energy and the smallest melting point among these three elements. What are the identities of Q, R and S?
Feb/March 2025
J can be $\text{MgCl}_2$ or $\text{AlCl}_3$. K can be $\text{SiO}_2$ or $\text{SiCl}_4$. $\text{J}(aq) \xrightarrow[]{\text{add drops of aqueous sodium hydroxide}}$ white precipitate $\xrightarrow[]{\text{add an excess of aqueous sodium hydroxide}}$ precipitate dissolves $\text{K} \xrightarrow[]{\text{add water}}$ misty white fumes and a white precipitate in a solution with $\text{pH} < 7$ Which row is the correct one?
Feb/March 2025
X and Y are elements in the same group of the Periodic Table. The 5th to 9th ionisation energies of X and Y are given. Ionisation energy / $\text{kJ mol}^{-1}$: Element X: 5th $11020$, 6th $15160$, 7th $17870$, 8th $92040$, 9th $106437$. Element Y: 5th $6540$, 6th $9360$, 7th $11020$, 8th $33360$, 9th $38600$. Which row is used to identify elements X and Y?
Feb/March 2025
The consecutive elements X, Y and Z are located in the third period of the Periodic Table. Element Y has the greatest first ionisation energy and the smallest melting point. What could be the identities of X, Y and Z?
May/June 2010
Which element in the third period needs the smallest number of moles of oxygen for the complete combustion of $1\,\text{mol}$ of the element?
May/June 2010
Two characteristics of non-metal elements and the atoms of those elements are given below. Characteristic 1: it forms an oxide that produces a strong acid in water. Characteristic 2: it has no paired $3p$ electrons. Which of these characteristics apply to phosphorus and sulfur?
May/June 2010
The elements radon (Rn), francium (Fr) and radium (Ra) have successive proton numbers in the Periodic Table. In what order do their first ionisation energies occur?
May/June 2010
Two characteristics of non-metal elements and their atoms are given below. property $1$ forms an oxide that can make a strong acid in water property $2$ does not have paired $3p$ electrons Which of these properties are shown by phosphorus and sulfur?
May/June 2010
Three neighbouring elements $X$, $Y$ and $Z$ are located in the third period of the Periodic Table. Element $Y$ has the greatest first ionisation energy and the lowest melting point. What might the identities of $X$, $Y$ and $Z$ be?
May/June 2010
Consulting the Data Booklet is useful for answering this question. In the Periodic Table, the elements radon (Rn), francium (Fr) and radium (Ra) are arranged in successive proton numbers. In which order do their first ionisation energies occur?
May/June 2010
The following are two characteristics of non-metallic elements and the atoms of those elements. property 1: forms an oxide that produces a strong acid when dissolved in water property 2: does not have paired $3p$ electrons Which of these properties are found in phosphorus and sulfur?
May/June 2010
Three successive elements X, Y and Z are located in the third period of the Periodic Table. Element Y has the greatest first ionisation energy and the smallest melting point. What could be the identities of X, Y and Z?
May/June 2010
The Data Booklet may be used for this question. The elements radon (Rn), francium (Fr) and radium (Ra) have consecutive proton numbers in the Periodic Table. In what order do their first ionisation energies increase?
May/June 2010
Chlorine, $\text{Cl}_2$, is a gas at room temperature, but bromine, $\text{Br}_2$, is a liquid under the same conditions. Explain these observations.
May/June 2010
This question is about the elements shown in the extract of the Periodic Table provided.
May/June 2010
Experimental evidence from the 19th and 20th centuries led scientists to conclude that atoms contain a positive, heavy nucleus with electrons around it. Later in the 20th century, theoretical scientists described how electrons are arranged in orbitals about atoms.
May/June 2010
Copper, proton number 29, and argon, proton number 18, are elements that differ in both physical and chemical properties. When solid, each one has the same face-centred cubic crystal structure, as shown below. The particles in such a crystal can be atoms, molecules, anions or cations. In the diagram above, the particles are shown by ●.
May/June 2010
The table below shows information about some oxides of Period 3 elements.
May/June 2010
The alkali metals make up six elements in Group I of the Periodic Table. Their first ionisation energy follows a clear pattern as the Group is descended.
May/June 2010
This item is about the elements shown in the Periodic Table extract below.
May/June 2010
Which factor accounts for the decrease in the first ionisation energies of the Group I elements as the sequence goes from lithium to sodium to potassium to rubidium?
May/June 2011
In $1999$, researchers in the USA thought that they had discovered a new element and suggested that it had this electronic configuration. $[\text{Rn}]\ 5f^{14}6d^{10}7s^27p^6$ In which Group of the Periodic Table would you expect this element to be in?
May/June 2011
The highest oxides of the elements from sodium to chlorine are each added separately to water. Which diagram shows the pH of the mixtures formed most accurately?
May/June 2011
The diagram illustrates the first ionisation energies for $11$ elements in a row. What type of elements are represented by X and Y?
May/June 2011
Why is aluminium oxide soluble in sodium hydroxide solution?
May/June 2011
Which factor accounts for the decrease in the first ionisation energies of the Group I elements from lithium to sodium to potassium to rubidium?
May/June 2011
Which oxides will react with water to form a solution whose pH is $10$ or above?
May/June 2011
The kinetic theory of gases explains the large-scale (macroscopic) characteristics of gases by examining the way individual molecules move.
May/June 2011
Elements in the same period of the Periodic Table display patterns in physical and chemical properties. The grids refer to the third-period elements, Na to Cl. On each grid, draw a clear sketch to show how the named property changes. Beneath each grid, briefly explain the variation shown in your sketch.
May/June 2011
Sodium and sulfur combine to produce sodium sulfide, $\text{Na}_2\text{S}$. How does the atomic radius of sodium compare with that of sulfur, and how does the ionic radius of sodium compare with that of sulfur?
May/June 2012
Oxides are compounds that normally consist of oxygen joined to one other element. They are grouped into these types: acidic, alkaline, amphoteric, basic.
May/June 2012
All third-period elements in the Periodic Table, from sodium to sulfur, form chlorides by direct combination.
May/June 2012
Although the exact size of an atom cannot be measured directly, the separation between the nuclei of two atoms can be measured. For example, the ‘covalent radius’ of the Cl atom is taken to be half the distance between the nuclei in a $\text{Cl}_2$ molecule. In a similar way, the ‘metallic radius’ is half the distance between two metal atoms in the crystal lattice of a metal. These two kinds of radius are generally referred to as ‘atomic radii’. The table below gives the atomic radii obtained for the period three elements of the Periodic Table, Na to Cl.
May/June 2012
The graph shows the first ionisation energies of twenty consecutive elements in the Periodic Table. The letters shown are not the usual symbols for these elements. Which of the following statements about the graph are correct?
May/June 2013
The elements radon (Rn), francium (Fr) and radium (Ra) have proton numbers 86, 87 and 88 respectively. How do their first ionisation energies rank in order?
May/June 2013
The graphs show the patterns for three physical properties of the elements Na, Mg, Al, Si, P and S. Which physical property is not shown?
May/June 2013
The first six ionisation energies for four elements are shown below. Which element is most likely to belong to Group IV of the Periodic Table?
May/June 2013
This question concerns the elements in the Periodic Table section illustrated below.
May/June 2013
This question is about the elements shown in the part of the Periodic Table provided.
May/June 2013
Using the Data Booklet is relevant for this question. Which graph shows relative electronegativity plotted against relative atomic radius correctly for the elements Na, Mg, Al and Si?
May/June 2014
The graph shows the relative values of the first ionisation energies for four elements with consecutive atomic numbers. One of these elements reacts with hydrogen to produce a covalent compound with the formula $\text{HX}$. Which element could be $X$?
May/June 2014
Use of the Data Booklet is relevant for this question. Which graph accurately displays the melting points of the elements Mg, Al, Si and P plotted against their first ionisation energies?
May/June 2014
The species Ne, $\text{Na}^+$ and $\text{Mg}^{2+}$ are isoelectronic. This indicates that they each contain the same number of electrons. In what sequence do their radii increase?
May/June 2014
What properties are shared by compounds of aluminium and silicon?
May/June 2014
In 2011, a group of scientists from around the world agreed to include two further elements in the Periodic Table. Both had been produced synthetically and were named ununquadium (Uuq) and ununhexium (Uuh). Which of the following statements about these elements is correct?
May/June 2014
Explain the meaning of ionisation energy.
May/June 2014
Explain what the term nucleon number means.
May/June 2014
What observations are seen when a sample of silicon chloride, $\text{SiCl}_4$, is placed into a beaker of water?
May/June 2015
The Data Booklet may be needed for this question. Which diagram accurately presents the atomic radii of Mg, Al, Si and P against their melting points?
May/June 2015
Which diagram accurately displays the electronegativity of the elements Na, Mg, Al and Si plotted against their first ionisation energies?
May/June 2015
When these oxides are added to water, which ones will make the water's pH change?
May/June 2015
Which oxide will form the solution with the highest $\text{pH}$ after being mixed with water?
May/June 2015
This question concerns isolated gaseous species. The species $\text{F}^-$, $\text{Ne}$ and $\text{Na}^+$ are isoelectronic, which means that each has the same number of electrons. In what order do their radii increase?
May/June 2015
Because lithium and magnesium have comparable ionic radii, the reactions of lithium and its compounds are very similar to those of magnesium and their corresponding compounds. Which statement about the reactions of lithium or its compounds can be predicted from this statement?
May/June 2015
Neon belongs to the noble gases.
May/June 2015
What makes the ionic radius of a chloride ion greater than the ionic radius of a sodium ion?
May/June 2016
Elements D and E both belong to Period 3. Within Period 3, element D has the smallest atomic radius. In Period 3, only two elements have a melting point lower than that of element E. Elements D and E combine to produce compound L. Which compound could be L?
May/June 2016
When sodium and sulfur combine, sodium sulfide, $\text{Na}_2\text{S}$, is produced. How does the atomic radius and the ionic radius of sodium compare with those of sulfur?
May/June 2016
Elements X and Y belong to the same group in the Periodic Table. The table gives the first six ionisation energies of X and Y in $\text{kJ mol}^{-1}$. What might the identities of X and Y be?
May/June 2016
The graph shows the first ionisation energies of twenty consecutive elements in the Periodic Table. The letters used here are not the standard symbols for these elements. Which of the following statements about this graph are correct?
May/June 2016
The oxide and chloride of an element $X$ are each combined separately with water. The two solutions formed have the same effect on litmus. Which element could $X$ be?
May/June 2016
Compound X contains two elements. One of them has the second-highest first ionisation energy value in its group, and the other has the third-highest first ionisation energy value in its group. Which compounds might compound X be?
May/June 2016
Why is the first ionisation energy of aluminium lower than that of magnesium?
May/June 2016
Fill in the table to show the composition and identity of some atoms and ions.
May/June 2016
D, E, F, and G form four successive elements in the fourth period of the Periodic Table. (The letters are not the real symbols of the elements.) D is a soft, shiny metal whose melting point is a little higher than room temperature. Its amphoteric oxide, $\text{D}_2\text{O}_3$, has a melting point of $1900^\circ\text{C}$ and may be obtained by heating D in oxygen. G is a solid that occurs in several allotropes, most of which consist of $\text{G}_8$ molecules. G burns in air to form $\text{GO}_2$, which dissolves in water to give an acidic solution. This solution reacts with sodium hydroxide to produce the salt $\text{Na}_2\text{GO}_3$.
May/June 2016
Complete the table so that the composition and identity of some atoms and ions are shown.
May/June 2016
Explain why the second ionisation energy of sodium is greater than the second ionisation energy of magnesium.
May/June 2017
Which statements describe a trend in Period 3 for each neighbouring pair of elements from sodium through to chlorine?
May/June 2017
Which property of an atom has no influence on its first ionisation energy?
May/June 2017
Magnesium and sulfur each produce ions with a 2+ charge. How do the atomic radii and ionic radii of these two elements compare?
May/June 2017
Which graph shows relative electronegativity plotted against relative atomic radius for the elements Na, Mg, Al and Si correctly?
May/June 2017
Magnesium chloride, $\text{MgCl}_2$, and silicon tetrachloride, $\text{SiCl}_4$, are each placed into water separately. What approximate pH values do the resulting solutions have?
May/June 2017
Which graph accurately displays the relative melting points of the elements Mg, Al, Si and P when plotted against their relative first ionisation energies?
May/June 2017
The characteristics of elements and the compounds they form display similarities, contrasts and patterns that depend on where the elements lie in the Periodic Table.
May/June 2017