Periodic Table MCQ Quiz - Objective Question with Answer for Periodic Table - Download Free PDF

CONCEPT:

Electronic Configuration of Transition Metals

• Transition metals are elements found in the d-block of the periodic table.
• These elements have partially filled d orbitals and typically show a variety of oxidation states.
• The electronic configuration of transition metals includes filling the 3d orbitals after the 4s orbitals.

EXPLANATION:

• Option A: [Ne]3s²3p⁶4s²3d⁶ is the electronic configuration of Iron (Fe), a transition metal, located in the d-block of the periodic table.
• Option B: [Ar]3d⁸4s² is the electronic configuration of Nickel (Ni), a transition metal, also found in the d-block.
• Option C: [Kr]4s²4d⁷5p³ is not a transition metal configuration. It corresponds to an element in the p-block (Arsenic, As), not a transition metal.
• Option D: [Xe]4f¹⁴5d⁷6s² is the electronic configuration of a lanthanide element (e.g., Dysprosium), not a transition metal, as it involves filling the 4f orbitals.

Therefore, the correct answer is: A and B only.

CONCEPT:

Trends in Ionic Sizes

• Ionic size is influenced by the number of protons, electrons, and electron-electron repulsion in an ion.
• In general:
  • Cations are smaller than their parent atoms due to the loss of electrons, resulting in reduced electron-electron repulsion and stronger attraction of the remaining electrons to the nucleus.
  • Anions are larger than their parent atoms due to the gain of electrons, increasing electron-electron repulsion and slightly weakening the attraction of the electrons to the nucleus.
• For isoelectronic species (ions with the same number of electrons), the ionic size decreases as the nuclear charge increases. This is because a higher nuclear charge pulls the electrons closer to the nucleus.

EXPLANATION:

• The ions F^-, Na⁺, O^2-, Al³⁺, and Mg²⁺ are isoelectronic (all have 10 electrons).
• The nuclear charges of these ions are as follows:
  • Al³⁺: +13
  • Mg²⁺: +12
  • Na⁺: +11
  • F^-: +9
  • O^2-: +8
• Higher nuclear charge results in stronger attraction of electrons to the nucleus, leading to smaller ionic size.
• Therefore, the correct order of increasing ionic size is:

  Al³⁺ < Mg²⁺ < Na⁺ < F^- < O^2-

Therefore, the correct answer is Al³⁺ < Mg²⁺ < Na⁺ < F^- < O^2-.

CONCEPT:

The International Union of Pure and Applied Chemistry (IUPAC) systematically assigns temporary names to newly discovered or synthesized elements based on their atomic numbers until permanent names are given. These temporary names follow specific guidelines.

• The naming convention uses Latin roots for the digits of the atomic number.
• The suffix "-ium" is added at the end for elements.
• Each digit of the atomic number is represented by a corresponding Latin root:
  • 1 = "un"
  • 2 = "bi"
  • 3 = "tri"
  • ... and so on.
• For example, for atomic number 112:
  • 1 = "un"
  • 1 = "un"
  • 2 = "bi"
• The temporary IUPAC name becomes "Ununbium."

EXPLANATION:

• The element with atomic number 112 was assigned the temporary name "Ununbium" following the IUPAC naming rules.
• In the given options:
  • "Unnilennium" is incorrect because it does not follow the correct naming convention for atomic number 112.
  • "Ununnilium" is incorrect; it corresponds to atomic number 110.
  • "Unununium" is incorrect; it corresponds to atomic number 111.
  • "Ununbium" is correct, as it follows the Latin roots for atomic number 112.

Therefore, the IUPAC name of the element with atomic number 112 is "Ununbium,".

The correct answer is: Option 1 (Statement I is false but Statement II is true)

CONCEPT:

• Metallic radius is the distance between the nuclei of two adjacent metal atoms.
• Across a period, metallic radius generally decreases due to increasing nuclear charge.
• Ga comes after Al in the periodic table (Group 13), and despite higher atomic number, Ga has a smaller than expected size due to d-electron poor shielding.
• However, Ga actually has a slightly smaller metallic radius than Al due to lanthanide contraction.
• Ionic radius of Al3+ is smaller than Ga3+ because it has fewer electrons and a smaller electron cloud for the same +3 charge.

EXPLANATION:

• Statement I: Incorrect. The metallic radius of Al (143 pm) is actually slightly greater than that of Ga (135 pm) due to lanthanide contraction affecting Ga.
• Statement II: Correct. Al3+ has fewer electrons than Ga3+, leading to stronger nuclear attraction and thus a smaller ionic radius.

Therefore, the correct analysis is: Statement I is false but Statement II is true.

CONCEPT:

Metallic Character

• Metallic character refers to the ability of an element to lose electrons and form positive ions (cations).
• Elements with higher metallic character are generally found on the left side of the periodic table and towards the bottom.
• Metallic character increases down a group and decreases across a period from left to right.

EXPLANATION:

• Potassium (K) is in Group 1, which has the highest metallic character.
  • Magnesium (Mg) is in Group 2, which also has high metallic character but less than Group 1.
  • Aluminum (Al) is in Group 13, which has moderate metallic character.
  • Boron (B) is in Group 13, but it is a metalloid with much lower metallic character compared to Al.
• Considering the position in the periodic table and the trend of metallic character:
  • K has the highest metallic character.
  • Mg has less metallic character than K but more than Al.
  • Al has less metallic character than Mg but more than B.
  • B has the lowest metallic character among the given elements.

Therefore, the correct order of metallic character is: K > Mg > Al > B.

The correct answer is 1.

The correct answer is Alkali metals 

Key Points

• Alkali metals:-
  • Alkali metals have the largest atomic size in their respective periods.
  • This translates to a weaker attraction between the positively charged nucleus and the outermost (valence) electron.
  • As a result, less energy is needed to remove this electron, leading to a lower ionization potential.

Additional Information

• Alkaline earth metals:-
  • These come after alkali metals in a period and while they are relatively large, they have two valence electrons compared to just one for alkali metals. 
  • This increases the effective nuclear charge experienced by the valence electrons, slightly raising their ionization potential compared to alkali metals.
• In contrast, halogens are on the rightmost side of the period and have one electron less than a full valence shell. They attract their valence electrons strongly, resulting in high ionization potentials.
• Inert gases have filled valence shells, achieving a stable configuration. Removing an electron from such a stable configuration requires a lot of energy, resulting in very high ionization potentials.

The correct answer is Potassium-Po.

Key Points

• Potassium:
  • ​Potassium is a chemical element with the symbol K.
  • The Atomic number of potassium is 19.
  • It is a silvery-white metal that is smooth enough to be sliced with little force with a knife.
  • Potassium reacts rapidly with atmospheric oxygen within seconds of exposure to form flaky, white potassium peroxide.

Additional Information

Phosphorus	Phosphorus is a chemical element with atomic number 15. The symbol of phosphorus is P. It was discovered by Hennig Brand in 1669.
Iron	Symbol Fe and atomic number = 26. Wrought Iron is the purest form of iron. The Most impure form of Iron is Pig Iron.
Iodine	Iodine is a chemical element with the symbol I and atomic number 53.  Iodine is a trace element that is naturally present in some foods, is added to some types of salt, and is available as a dietary supplement.

The correct answer is Nihonium.Key Points

• The element with atomic number 113 belongs to group 13 of the periodic table, which is also known as the boron group.
• The electronic configuration [Rn] 5f¹⁴6d¹⁰7s²7p¹ belongs to the element Nihonium, which was officially named in 2016 and is a synthetic element that is not found naturally on Earth.
• Nihonium is a highly unstable and radioactive element, with a very short half-life of only a few seconds, and its properties are still being studied by scientists.

Additional Information

• Group 13 elements are characterized by having three valence electrons in their outermost shell, which makes them reactive and able to form compounds with other elements.
• Gallium is a soft, silvery metal that has a low melting point and is used in a variety of applications, such as in semiconductors, LEDs, and alloys.
• Indium is a rare, silvery-white metal that is used in electronics, as well as in coatings, alloys, and other industrial applications.
• Thallium is a toxic, bluish-white metal that is used in electronics, as well as in pesticides, rodenticides, and other chemicals.
• It is also a radioactive isotope that is used in medical imaging.
• Thallium is also a group 13 element, but it has a higher atomic number than Nihonium and a different electronic configuration.

Concept:

• Nuclear charge: The nuclear charge is the total charge of all the protons in the nucleus.

Nuclear charge of Boron (B) > Nuclear charge of Be

First ionization enthalpy:

Be = 1s² 2s² (more stable)

B = 1s² 2s² 2p¹

The first ionization of Beryllium is greater than that of boron because beryllium has a stable complete electronic configuration (1s² 2s²) so it requires more energy to remove the first electron from it. Whereas boron has the electronic configuration 1s² 2s² 2p¹ which needs lesser energy than that of beryllium to remove the valence electron.

∴ Ionisation energy of Be is greater than B due to ns² outer electronic configuration.

The ionization energy is the energy required to remove an electron from its orbital around an atom to a point where it is no longer associated with that atom. The ionization energy of an element increases as one moves across the period in the periodic table because the electron is held tighter by the higher effective nuclear charge.

The correct answer is Li and Mg. Key Points

• Lithium (Li) and Magnesium (Mg) show a diagonal relationship as they are located diagonally opposite to each other in the periodic table.
• Both Li and Mg have similar atomic radii, electronegativities, and ionization energies due to the similarities in their electronic configurations.
• A diagonal relationship refers to the similarities in properties between elements that are diagonally opposite to each other in the periodic table.

Additional Information

• Diagonal relationship is a result of the similarities in the electronic configurations of these elements.
• Be and B do not show a diagonal relationship as they are not located diagonally opposite to each other in the periodic table.
• Similarly, Be and Mg do not show a diagonal relationship as they belong to the same group and have different electronic configurations.
• Na and Mg also do not show a diagonal relationship as they belong to different periods and have different electronic configurations.

Concept: -

• Modern Periodic Table has 18 Groups and 7 Periods.
• It has 118 Elements.
• Each of the tables has a vertical row called a group. Elements in groups have similar chemical and physical properties because they have the same number of outer electrons.
• Each of the tables has horizontal rows called periods. During a period, a gradual change in chemical properties occurs from one element to another.
• The elements are arranged in the modern periodic table on the basis of Mosely's law, which states that the physical and chemical properties of elements are the periodic function of their atomic number.
• The Structure of it is like a bird Grid.
• The Modern Periodic table is used to organize all the known elements.
• Advantages of Modern Periodic Table:- 
  • It is easier to remember the properties of an element if its position in the periodic table is known.
  • It made the study of Chemistry Systematic and Easy.

Modern Periodic Table:-

Explanation: -

A period in the periodic table represents the principal quantum number.

As Principal quantum numbers stay the same moving left to right in the rows of the periodic table.

So, the shell remains same in a periodic table, while moving from left to right in a period.

Hence, the correct answer is a shell, option 3.

Concept:

The pair that has similar atomic radii is Mo and W because Mo and W belong to group-6 and period-5 (4d series), period-6 (5d series) respectively, Due to the lanthanoid contraction, the radius of Mo and W are almost the same i.e. 0.140 nm and 0.141 nm respectively.

Lanthanoid contraction is the steady decrease in the size of the atoms and ions of the rare earth elements with increasing atomic number from lanthanum (atomic number 57) through lutetium (atomic number 71).

Molybdenum (Mo) is a chemical element with the symbol Mo and atomic number 42.

Molybdenum does not occur naturally as a free metal on Earth, it is found only in various oxidation states in minerals. The free element, silvery metal with a grey cast, has the sixth-highest melting point of any element. It readily forms hard, stable carbides in alloys.

Tungsten or wolfram is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively combined with other elements in chemical compounds rather than alone. Its important ores include wolframite and scheelite.

The correct answer is option 4.

Key Points

• Symbols of Dalton's elements:
  • Dalton, the father of modern atomic theory, was the first to use symbols to represent elements.
  • Dalton symbols were generally circles with different symbols such as a dot for hydrogen, a cross for sulfur or circles with letters such as C for copper, L for lead, etc.
  • The various symbols used by Dalton to represent different elements are as follows;

Concept: -

Atomic number

• It plays a very important role in the placement of elements in the modern periodic table.
• It represents the number of protons and hence the number of electrons in an atom.
• The number of electrons in an atom governs its chemical behavior.
• The study of elements has revealed their applicability in different forms.
• The number of protons present in the nucleus of an atom is called the atomic number. It is generally represented by Z.
• It has been established that the charge of a proton is equal to but opposite to that of an electron.
• Since an atom is electrically neutral and neutrons carry no electrical charge, the number of electrons and protons in a neutral atom is the same.
• This implies that the atomic number is equal to the number of protons or the number of electrons in an atom.
• As we know that elements tend to lose or gain electrons during many chemical reactions, and the number of protons is conventionally used to represent the atomic number of an element. 
• Hydrogen has an atomic number of one as it has only one proton in its atom.

Explanation: -

Let's Look at the periodic table: -

So,  the atomic number of Aluminum, silicon, chlorine, and Magnesium is 13, 14, 17, and 12 respectively.

Conclusion: -

The Atomic Nuber of Phosphorous is 15. So, the atomic number of Cl will be more than Phosphorous.

Hence, the correct option is (3), Chlorine.