NEET Chemistry Classification Of Elements and Periodicity In Properties MCQs Set A

Question:  What is the value of electron gain enthalpy of Na⁺ if IE₁ of Na = 5.1 eV? 

• a) +2.55 eV
• b) +10.2 eV
• c) –5.1 eV
• d) –10.2 eV

Answer: –5.1 eV

Question: Which one of the following arrangements represents the correct order of electron gain enthalpy (with negative sign) of the given atomic species ?

• a) Cl < F < S < O
• b) O < S < F < Cl
• c) S < O < Cl < F
• d) F < Cl < O < S

Answer: O < S < F < Cl

Question: Among the elements Ca, Mg, P and Cl, the order of increasing atomic radii is

• a) Mg < Ca < Cl < P
• b) Cl < P < Mg < Ca
• c) P < Cl < Ca < Mg
• d) Ca < Mg < P < Cl

Answer: Cl < P < Mg < Ca

Question: Which one of the following arrangements represents the correct order of least negative to most negative electron gain enthalpy for C, Ca, Al, F and O?

• a) Ca < Al < C < O < F
• b) Al < Ca < O < C < F
• c) Al < O < C < Ca < F
• d) C < F < O < Al < Ca

Answer: Ca < Al < C < O < F

Question:  The electronic configuration of an element is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p². What is the atomic number of the element, which is just below the above element in the periodic table?

• a) 36
• b) 49
• c) 50
• d) 54

Answer: 50

Question: Which of the following ion is the largest in size?

• a) K⁺
• b) Ca²⁺
• c) Cl^– 
• d) S^–2

Answer:  S^–2

Question: The electronic configuration of inner transition elements is

• a) ns¹ 
• b) ns²np⁵nd¹⁰  
• c) ns^0–2 (n – 1) d^1–10 (n – 2) f^1–14
• d) ns² (n – 1) d^0–1 (n – 2) f^1–14

Answer:  ns² (n – 1) d^0–1 (n – 2) f^1–14

Question: Which of the following has the smallest size?

• a) Al³⁺
• b) F^– 
• c) Na⁺
• d) Mg²⁺

Answer:  Al³⁺

Question: The first ionization potentials (eV) of N and O respectively are

• a) 8.29, 8.29
• b) 11.32, 11.32
• c) 8.29, 11.32
• d) 11.32, 8.21

Answer: 11.32, 8.21

Question: Which one of the following is correct order of the size of aluminium species?

• a) Al > Al⁺ > Al²⁺
• b) Al²⁺ > Al⁺ > Al 
• c) Al²⁺ = Al⁺ = Al
• d) All of these

Answer:  Al > Al⁺ > Al²⁺

More Questions............................................

Question:  Correct order of I^st ionization potential among elements Be, B, C, N, O is

• a) B < Be < C < O < N
• b) B < Be < C < N < O
• c) Be < B < C < N < O
• d) Be < B < C < O < N

Answer: B < Be < C < O < N

Question:  An atom has electronic configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 3d³ 4s², you will place it in which group of periodic table?

• a) Fifth
• b) Fifteenth
• c) Second
• d) Third

Answer: Fifth

Question: Ionic radii are

• a) Inversely proportional to effective nuclear charge
• b) Inversely proportional to square of effective nuclear charge
• c) Directly proportional to effective nuclear charge
• d) Directly proportional to square of effective nuclear charge

Answer: Inversely proportional to effective nuclear charge

Question: Four successive members of the first row transition elements are listed below with their atomic numbers. Which one of them is expected to have the highest third ionisation enthalpy?

• a) Vanadium (Z = 23)
• b) Chromium (Z = 24)
• c) Manganese (Z = 25)
• d) Iron (Z = 26)

Answer: Manganese (Z = 25)

Question: The element with highest electronegativity will belong to

• a) Period 2, group 17
• b) Period 3, group 17
• c) Period 2, group 18
• d) Period 2, group 1

Answer: Period 2, group 17

Question:  The first, second and third ionisation energies of Al are 578, 1817 and 2745 kJ mol^–1 respectively. Calculate the energy required to convert all the atoms of Al to Al⁺³ present in 270 mg of Al vapours

• a) 5140 kJ
• b) 51.40 kJ
• c) 2745 kJ
• d) 514.0 kJ

Answer: 51.40 kJ

Question: The size of ionic species is correctly given in the order

• a) Na⁺ > Mg⁺² > Cl⁺⁷ > Si⁴⁺
• b) N^a+ > Mg⁺² > Si⁴⁺ > Cl⁺⁷
• c) Cl⁺⁷ > Si⁺⁴ > Mg⁺² > Na⁺ 
• d) Cl⁺⁷ > Na⁺ > Mg⁺² > Si⁺⁴

Answer:  N^a+ > Mg⁺² > Si⁴⁺ > Cl⁺⁷

Question:  Match the following, regarding nature of the oxides

• a) a(ii), b(i), c(iii), d(iv)
• b) a(iv), b(i), c(iii), d(ii)
• c) a(iv), b(i), c(ii), d(iii)
• d) a(ii), b(i), c(iv), d(iii)

Answer: a(iv), b(i), c(ii), d(iii)

Question:   Be²⁺ is isoelectronic with which of the following ions?

• a) H⁺
• b) Li⁺
• c) Na⁺
• d) Mg²⁺

Answer:  Li⁺

Question: The element with highest electronegativity will belong to

• a) Period 2, group 17
• b) Period 3, group 17
• c) Period 2, group 18
• d) Period 2, group 1

Answer: Period 2, group 17

Question: Four successive members of the first row transition elements are listed below with their atomic numbers. Which one of them is expected to have the highest third ionisation enthalpy?

• a) Vanadium (Z = 23)
• b) Chromium (Z = 24)
• c) Manganese (Z = 25)
• d) Iron (Z = 26)

Answer: Manganese (Z = 25)

Question: Ionic radii are

• a) Inversely proportional to effective nuclear charge
• b) Inversely proportional to square of effective nuclear charge
• c) Directly proportional to effective nuclear charge
• d) Directly proportional to square of effective nuclear charge

Answer: Inversely proportional to effective nuclear charge

Question: The first ionization potentials (eV) of N and O respectively are

• a) 8.29, 8.29
• b) 11.32, 11.32
• c) 8.29, 11.32
• d) 11.32, 8.21

Answer: 11.32, 8.21

Question: Which one of the following arrangements represents the correct order of electron gain enthalpy (with negative sign) of the given atomic species ?

• a) Cl < F < S < O
• b) O < S < F < Cl
• c) S < O < Cl < F
• d) F < Cl < O < S

Answer: O < S < F < Cl

Question: Identify the wrong statement in the following.

• a) Atomic radius of the elements increases as one moves down the first group of the periodic table
• b) Atomic radius of the elements decreases as one moves across from left to right in the 2nd period of the periodic table
• c) Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius
• d) Amongst isoelectronic species, greater the negative charge on the anion, larger is the ionic radius

Answer: Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius

Question: Which of the following is correct order of metallic character for Si, Be, Mg, Na and P?

• a) P < Si < Be < Na < Mg
• b) P < Si < Be < Mg < Na
• c) Na > Be > Mg > Be > P
• d) Na > Si > Mg > Be > P

Answer: P < Si < Be < Mg < Na

Question: Total number of elements present in 5th period of modern periodic table is

• a) 2
• b) 8
• c) 18
• d) 32

Answer: 18

Question: An atom of an element has electronic configuration 2, 8, 1. Which of the following statement is correct?

• a) The valency of element is 7
• b) The element exists as a triatomic molecule
• c) The element is metalloid
• d) The element forms basic oxide

Answer: The element forms basic oxide

Question: The electronic configurations of the elements X, Y, Z and J are given below. Which element has the highest metallic character?

• a) X = 2, 8, 4
• b) Y = 2, 8, 8
• c) Z = 2, 8, 8, 1
• d) J = 2, 8, 8, 7

Answer: Z = 2, 8, 8, 1

Question: The element with highest electron affinity will belong to

• a) Period 2, group 17
• b) Period 3, group 17
• c) Period 2, group 18
• d) Period 2, group 1

Answer: Period 3, group 17