Grade 11 : Chemistry - Periodic Table (Set 3)

Question 1

Modern Periodic Law states that the physical and chemical properties of elements are periodic functions of their:

Accepted Answer

B) Atomic number

Answer

A) Atomic mass

Answer

C) Mass number

Answer

D) Neutron-to-proton ratio

Question 2

According to the IUPAC systematic nomenclature for elements with $Z > 100$, what is the official name of the element with atomic number 118?

Accepted Answer

A) Ununoctium

Answer

B) Unnilseptium

Answer

C) Unhexium

Answer

D) Unbinilium

Question 3

Which of the following isoelectronic species has the smallest ionic radius?

Accepted Answer

D) $Mg^{2+}$

Answer

A) $N^{3-}$

Answer

B) $F^-$

Answer

C) $Na^+$

Question 4

Among the Period 2 elements Nitrogen ($N$), Oxygen ($O$), Carbon ($C$), and Boron ($B$), which element has the highest first ionization enthalpy ($ ext{IE}_1$)?

Accepted Answer

A) Nitrogen ($N$)

Answer

B) Oxygen ($O$)

Answer

C) Carbon ($C$)

Answer

D) Boron ($B$)

Question 5

Why does Chlorine (Cl) have a more negative electron gain enthalpy ($\Delta_{eg}H$) than Fluorine ($F$)?

Accepted Answer

B) Strong inter-electronic repulsions exist in the compact 2p subshell of Fluorine

Answer

A) Chlorine has a smaller atomic size than Fluorine

Answer

C) Fluorine has higher metallic character than Chlorine

Answer

D) Chlorine has a lower effective nuclear charge

Question 6

An element has an atomic number of $Z = 37$. To which block and group of the modern periodic table does it belong?

Accepted Answer

C) s-block, Group 1

Answer

A) p-block, Group 15

Answer

B) d-block, Group 5

Answer

D) f-block, Group 3

Question 7

Which of the following pairs of elements exhibits a diagonal relationship due to similar ionic potential (charge-to-radius ratio)?

Accepted Answer

D) Both B and C

Answer

A) Li and Na

Answer

B) Be and Al

Answer

C) $B$ and Si

Question 8

Which of the following oxides shows amphoteric behavior by reacting with both acids and bases?

Accepted Answer

C) $Al_2O_3$

Answer

A) $Na_2O$

Answer

B) $Cl_2O_7$

Answer

D) $SO_3$

Question 9

On the Pauling scale, electronegativity ($X_P$) is related to Mulliken electronegativity ($X_M$, measured in eV) by which formula?

Accepted Answer

A) $X_P = \frac{X_M}{2.8}$

Answer

B) $X_P = 2.8 	imes X_M$

Answer

C) $X_P = X_M - 2.8$

Answer

D) $X_P = \frac{X_M}{0.35}$

Question 10

The second ionization enthalpy ($ ext{IE}_2$) of Sodium (Na) is significantly higher than that of Magnesium (Mg) primarily because:

Accepted Answer

B) Removing a second electron from $Na^+$ breaks a stable noble gas core configuration ($1s^2 2s^2 2p^6$)

Answer

A) Sodium loses a valence s-electron in the second step

Answer

C) Magnesium has a smaller atomic radius than Sodium

Answer

D) Sodium has lower effective nuclear charge than Magnesium

Question 11

Which of the following correct sequences represents the increasing order of first ionization enthalpy ($ ext{IE}_1$) for Period 3 elements?

Accepted Answer

A) $Na < Al < Mg < Si < S < P < Cl < Ar$

Answer

B) $Na < Mg < Al < Si < P < S < Cl < Ar$

Answer

C) $Na < Al < Mg < Si < P < S < Cl < Ar$

Answer

D) $Na < Mg < Al < Si < S < P < Cl < Ar$

Question 12

The phenomenon of Lanthanoid Contraction is directly responsible for which observed periodic trend?

Accepted Answer

A) Zirconium (Zr) and Hafnium (Hf) having nearly identical atomic radii

Answer

B) Fluorine having higher electronegativity than Chlorine

Answer

C) Sodium and Potassium having similar standard reduction potentials

Answer

D) Nitrogen forming stable diatomic molecules while Phosphorus forms $P_4$

Question 13

Statement I: Fluorine is the most electronegative element in the modern periodic table.
Statement II: Fluorine has the most negative electron gain enthalpy among all halogens.

Evaluate Statements I and II and select the correct option:

Accepted Answer

B) Statement I is correct, but Statement II is incorrect.

Answer

A) Both Statement I and Statement II are correct.

Answer

C) Statement I is incorrect, but Statement II is correct.

Answer

D) Both Statement I and Statement II are incorrect.

Question 14

An element has a ground state valence electron configuration of $3d^5 4s^1$. What is its position in terms of Period and Group in the periodic table?

Accepted Answer

A) Period 4, Group 6

Answer

B) Period 3, Group 5

Answer

C) Period 4, Group 11

Answer

D) Period 3, Group 6

Question 15

Which of the following Group 2 alkaline earth metal ions has the highest hydration enthalpy?

Accepted Answer

D) $Be^{2+}$

Answer

A) $Ba^{2+}$

Answer

B) $Sr^{2+}$

Answer

C) $Ca^{2+}$

Question 16

Ion Label	Ionic Radius (pm)
P	140
Q	133
R	102
S	72

The table above lists the ionic radii of four isoelectronic species: $O^{2-}$, $F^-$, $Na^+$, and $Mg^{2+}$. Identify the ions labeled P and S respectively.

Accepted Answer

B) P = $O^{2-}$, S = $Mg^{2+}$

Answer

A) P = $Mg^{2+}$, S = $O^{2-}$

Answer

C) P = $F^-$, S = $Na^+$

Answer

D) P = $Na^+$, S = $F^-$

Question 17

What is the correct order of screening (shielding) effect exerted by orbitals of the same principal quantum shell $n$ on outer electrons?

Accepted Answer

A) $s > p > d > f$

Answer

B) $f > d > p > s$

Answer

C) $s < p < d < f$

Answer

D) $p > s > d > f$

Question 18

Which of the following alkali metals exhibits the highest electropositive (metallic) character?

Accepted Answer

B) Cesium (Cs)

Answer

A) Lithium (Li)

Answer

C) Potassium ($K$)

Answer

D) Sodium (Na)

Question 19

What is the oxidation state of Chlorine in $Cl_2O_7$, and what is the chemical nature of this oxide?

Accepted Answer

B) +7, Strongly acidic oxide

Answer

A) +7, Basic oxide

Answer

C) +5, Amphoteric oxide

Answer

D) +1, Neutral oxide

Question 20

For a neutral atom with ground state electronic configuration $1s^2 2s^2 2p^6 3s^2 3p^4$, how many unpaired electrons are present in its valence shell?

Accepted Answer

C) 2

Answer

A) 0

Answer

B) 1

Answer

D) 4

Grade 11 : Chemistry - Periodic Table (Set 3)