In period 4 of the periodic table, the elements with highest and lowest atomic radii are respectively.

The correct order of $\mathrm{C}, \mathrm{N}, \mathrm{O}$ and F in terms of second ionisation potential is

Given below are two statements :

Statement I : $\mathrm{K}>\mathrm{Mg}>\mathrm{Al}>\mathrm{B}$ is the correct order in terms of metallic character.

Statement II : Atomic radius is always greater than the ionic radius for any element.

In the light of the above statements, choose the correct answer from the options given below

Given below are two statements :

Statement I : The second ionisation enthalpy of Na is larger than the corresponding ionisation enthalpy of Mg .

Statement II : The ionic radius of $\mathrm{O}^{2-}$ is larger than that of $\mathrm{F}^{-}$.

In the light of the above statements, choose the correct answer from the options given below :

Elements X and Y belong to Group 15. The difference between the electronegativity values of ' X ' and phosphorus is higher than that of the difference between phosphorus and ' Y '. ' X ' & ' Y ' are respectively

The correct trend in the first ionization enthalpies of the elements in the $3^{\text {rd }}$ period of periodic table is :

Given below are two statements :

Statement I : $\mathrm{C}<\mathrm{O}<\mathrm{N}<\mathrm{F}$ is the correct order in terms of first ionization enthalpy values.

Statement II : $\mathrm{S}>\mathrm{Se}>\mathrm{Te}>\mathrm{Po}>\mathrm{O}$ is the correct order in terms of the magnitude of electron gain enthalpy values.

In the light of the above statements, choose the correct answer from the options given below :

Given below are two statements :

Statement I : The correct order in terms of atomic/ionic radii is Al > Mg > Mg²⁺ > Al³⁺.

Statement II : The correct order in terms of the magnitude of electron gain enthalpy is Cl > Br > S > O.

In the light of the above statements, choose the correct answer from the options given below :

Which of the following represents the correct trend for the mentioned property?

A. F > P > S > B      - First Ionization Energy

B. Cl > F > S > P      - Electron Affinity

C. K > Al > Mg > B      - Metallic character

D. K₂O > Na₂O > MgO > Al₂O₃      - Basic character

Choose the correct answer from the options given below :

$ \text { Match List - I with List - II. } $

Choose the correct answer from the options given below :

In a period, the first ionisation enthalpy of the element at extreme left and the negative electron gain enthalpy of the extreme right element, except noble gases, are respectively.

Given below are two statements :

Statement I : The number of pairs among $\left[\mathrm{Al}_2 \mathrm{O}_3, \mathrm{Cr}_2 \mathrm{O}_3\right],\left[\mathrm{Cl}_2 \mathrm{O}_7, \mathrm{Mn}_2 \mathrm{O}_7\right],\left[\mathrm{Na}_2 \mathrm{O}, \mathrm{V}_2 \mathrm{O}_3\right]$ and $\left[\mathrm{CO}, \mathrm{N}_2 \mathrm{O}\right]$ that contain oxides of same nature (acidic, basic, neutral or amphoteric) is 4 .

Statement II : Among $\mathrm{Na}_2 \mathrm{O}, \mathrm{Al}_2 \mathrm{O}_3, \mathrm{CO}$ and $\mathrm{Cl}_2 \mathrm{O}_7$, the most basic and acidic oxides are $\mathrm{Na}_2 \mathrm{O}$ and $\mathrm{Cl}_2 \mathrm{O}_7$, respectively.

In the light of the above statements, choose the correct answer from the options given below :

Given below are two statements:

Statement I: The correct order of electronegativity of fluorine, oxygen and nitrogen is $\mathrm{F}>\mathrm{O}>\mathrm{N}$.

Statement II: The oxidation state of oxygen in $\mathrm{OF}_2$ is +2 and in $\mathrm{Na}_2 \mathrm{O}$ is -2 .

In the light of the above statements, choose the correct answer from the options given below

The $1^{\text {st }}$ ionization enthalpy for Mg is $+737 \mathrm{~kJ} / \mathrm{mol}$. The most probable estimated value of the $2^{\text {nd }}$ ionization enthalpy of Mg is $\_\_\_\_$ .

The correct set that contains all kinds (basic, acidic, amphoteric and neutral) of oxides is :

Given below are two statements :

Statement (I) : The first ionisation enthalpy of the elements Na, Mg, Cl and Ar follows the order Na > Mg > Cl > Ar.

Statement (II) : Among Ca, Al, Fe and B, the third ionisation enthalpy is very high for Ca.

In the light of the above statements, choose the correct answer from the options given below :

The atomic number of the element from the following with lowest 1^st ionisation enthalpy is :

Given below are two statements:

Statement I: H₂Se is more acidic than H₂Te

Statement II: H₂Se has higher bond enthalpy for dissociation than H₂Te

In the light of the above statements, choose the correct answer from the options given below:

Choose the incorrect trend in the atomic radii (r) of the elements.

The number of valence electrons present in the metal among $\mathrm{Cr}, \mathrm{Co}, \mathrm{Fe}$ and Ni which has the lowest enthalpy of atomisation is :

The group 14 elements $A$ and $B$ have the first ionisation enthalpy values of 708 and $715 \mathrm{~kJ} \mathrm{~mol}^{-1}$ respectively. The above values are lowest among their group members. The nature of their ions $\mathrm{A}^{2+}$ and $\mathrm{B}^{4+}$ respectively is

The incorrect relationship in the following pairs in relation to ionisation enthalpies is :

The elements of Group 13 with highest and lowest first ionisation enthalpies are respectively :

The correct orders among the following are

Atomic radius : $\mathrm{B}<\mathrm{Al}<\mathrm{Ga}<\mathrm{In}<\mathrm{Tl}$

Electronegativity : $\mathrm{Al}<\mathrm{Ga}<\mathrm{In}<\mathrm{Tl}<\mathrm{B}$

Density : $\mathrm{Tl}<\mathrm{In}<\mathrm{Ga}<\mathrm{Al}<\mathrm{B}$

1st Ionisation Energy : $\mathrm{In}<\mathrm{Al}<\mathrm{Ga}<\mathrm{Tl}<\mathrm{B}$

Choose the correct answer from the options given below:

$ \text { Match the LIST-I with LIST-II } $

Which of the following statements are correct?

A. The process of adding an electron to a neutral gaseous atom is always exothermic.

B. The process of removing an electron from an isolated gaseous atom is always endothermic.

C. The $1^{\text {st }}$ ionization energy of boron is less than that of beryllium.

D. The electronegativity of C is 2.5 in $\mathrm{CH}_4$ and $\mathrm{CCl}_4$

E. Li is the most electropositive among elements of group I.

Choose the correct answer from the options given below:

Electronic configuration of four elements A, B, C and D are given below :

(A) $1 s^2 2 s^2 2 p^3$

(B) $1 s^2 2 s^2 2 p^4$

(C) $1 s^2 2 s^2 2 p^5$

(D) $1 s^2 2 s^2 2 p^2$

Which of the following is the correct order of increasing electronegativity (Pauling's scale)?

Given below are two statements :

Statement (I) : The metallic radius of Al is less than that of Ga .

Statement (II) : The ionic radius of $\mathrm{Al}^{3+}$ is less than that of $\mathrm{Ga}^{3+}$.

In the light of the above statements, choose the most appropriate answer from the options given below :

The property/properties that show irregularity in first four elements of group-17 is/are

(A) Covalent radius

(B) Electron affinity

(C) Ionic radius

(D) First ionization energy

Choose the correct answer from the options given below :

The type of oxide formed by the element among Li, Na, Be, Mg, B and Al that has the least atomic radius is :

First ionisation enthalpy values of first four group 15 elements are given below. Choose the correct value for the element that is a main component of apatite family :

An element ‘E’ has the ionisation enthalpy value of 374 kJ mol⁻¹. ‘E’ reacts with elements A, B, C and D with electron gain enthalpy values of −328, −349, −325 and −295 kJ mol⁻¹, respectively. The correct order of the products EA, EB, EC and ED in terms of ionic character is :

Given below are two statements :

Statement (I) : The radii of isoelectronic species increases in the order.

Mg²⁺ < Na⁺ < F^$-$ < O^2-

Statement (II) : The magnitude of electron gain enthalpy of halogen decreases in the order.

Cl > F > Br > I

In the light of the above statements, choose the most appropriate answer from the options given below :

Given below are two statements :

Statement I : According to the Law of Octaves, the elements were arranged in the increasing order of their atomic number.

Statement II : Meyer observed a periodically repeated pattern upon plotting physical properties of certain elements against their respective atomic numbers.

In the light of the above statements, choose the correct answer from the options given below :

The incorrect decreasing order of atomic radii is

Consider the following elements $\mathrm{In}, \mathrm{Tl}, \mathrm{Al}, \mathrm{Pb}, \mathrm{Sn}$ and Ge . The most stable oxidation states of elements with highest and lowest first ionisation enthalpies, respectively, are

The successive 5 ionisation energies of an element are $800,2427,3658,25024$ and $32824 \mathrm{~kJ} / \mathrm{mol}$, respectively. By using the above values predict the group in which the above element is present :

Given below are two statements :

Statement (I) : The first ionization energy of Pb is greater than that of Sn .

Statement (II) : The first ionization energy of Ge is greater than that of Si .

In the light of the above statements, choose the correct answer from the options given below :

Which of the following statements are NOT true about the periodic table?

A. The properties of elements are function of atomic weights.

B. The properties of elements are function of atomic numbers.

C. Elements having similar outer electronic configurations are arranged in same period.

D. An element's location reflects the quantum numbers of the last filled orbital.

E. The number of elements in a period is same as the number of atomic orbitals available in energy level that is being filled.

Choose the correct answer from the options given below:

Given below are the atomic numbers of some group 14 elements. The atomic number of the element with lowest melting point is :

The element that does not belong to the same period of the remaining elements (modern periodic table) is:

Given below are two statements :

Statement (I) : An element in the extreme left of the periodic table forms acidic oxides.

Statement (II) : Acid is formed during the reaction between water and oxide of a reactive element present in the extreme right of the periodic table.

In the light of the above statements, choose the correct answer from the options given below :

Match List-I with List-II.

Choose the correct answer from the options given below :

Which of the following electronegativity order is incorrect?

Match List I with List II

Choose the correct answer from the options given below:

Match List I with List II

Choose the correct answer from the options given below:

Given below are two statements :

Statement (I) : The oxidation state of an element in a particular compound is the charge acquired by its atom on the basis of electron gain enthalpy consideration from other atoms in the molecule.

Statement (II) : $\mathrm{p} \pi-\mathrm{p} \pi$ bond formation is more prevalent in second period elements over other periods.

In the light of the above statements, choose the most appropriate answer from the options given below :

Choose the correct answer from the options given below:

The electron affinity value are negative for

A. $\mathrm{Be} \rightarrow \mathrm{Be}^{-}$

B. $\mathrm{N} \rightarrow \mathrm{N}^{-}$

C. $\mathrm{O} \rightarrow \mathrm{O}^{2-}$

D. $\mathrm{Na} \rightarrow \mathrm{Na}^{-}$

E. $\mathrm{Al} \rightarrow \mathrm{Al}^{-}$

Choose the most appropriate answer from the options given below :

Given below are two statements :

Statement I : The metallic radius of $\mathrm{Na}$ is $1.86 \mathrm{~A}^{\circ}$ and the ionic radius of $\mathrm{Na}^{+}$ is lesser than $1.86 \mathrm{~A}^{\circ}$

Statement II : Ions are always smaller in size than the corresponding elements.

In the light of the above statements, choose the correct answer from the options given below :

Given below are two statements:

Statement I: In group 13, the stability of +1 oxidation state increases down the group.

Statement II : The atomic size of gallium is greater than that of aluminium.

In the light of the above statements, choose the most appropriate answer from the options given below :

The statement(s) that are correct about the species $\mathrm{O}^{2-}, \mathrm{F}^{-}, \mathrm{Na}^{+}$ and $\mathrm{Mg}^{2+}$.

(A) All are isoelectronic

(B) All have the same nuclear charge

(C) $\mathrm{O}^{2-}$ has the largest ionic radii

(D) $\mathrm{Mg}^{2+}$ has the smallest ionic radii

Choose the most appropriate answer from the options given below :

The correct order of the first ionization enthalpy is

Given below are two statements :

Statement I : The correct order of first ionization enthalpy values of $\mathrm{Li}, \mathrm{Na}, \mathrm{F}$ and $\mathrm{Cl}$ is $\mathrm{Na}<\mathrm{Li}<\mathrm{Cl}<\mathrm{F}$.

Statement II : The correct order of negative electron gain enthalpy values of $\mathrm{Li}, \mathrm{Na}, \mathrm{F}$ and $\mathrm{Cl}$ is $\mathrm{Na}<\mathrm{Li}<\mathrm{F}<\mathrm{Cl}$

In the light of the above statements, choose the correct answer from the options given below :

The correct order of first ionization enthalpy values of the following elements is :

(A) O

(B) N

(C) Be

(D) F

(E) B

Choose the correct answer from the options given below :

Number of elements from the following that CANNOT form compounds with valencies which match with their respective group valencies is ________. B, C, N, S, O, F, P, Al, Si

Consider the following elements.

Which of the following is/are true about $\mathrm{A}^{\prime}, \mathrm{B}^{\prime}, \mathrm{C}^{\prime}$ and $\mathrm{D}^{\prime}$ ?

A. Order of atomic radii: $\mathrm{B}^{\prime}<\mathrm{A}^{\prime}<\mathrm{D}^{\prime}<\mathrm{C}^{\prime}$

B. Order of metallic character: $\mathrm{B}^{\prime}<\mathrm{A}^{\prime}<\mathrm{D}^{\prime}<\mathrm{C}^{\prime}$

C. Size of the element: $\mathrm{D}^{\prime}<\mathrm{C}^{\prime}<\mathrm{B}^{\prime}<\mathrm{A}^{\prime}$

D. Order of ionic radii: $\mathrm{B}^{\prime+}<\mathrm{A}^{1^{+}}<\mathrm{D}^{\prime+}<\mathrm{C}^{+}$

Choose the correct answer from the options given below :

The correct sequence of electron gain enthalpy of the elements listed below is

A. Ar

B. Br

C. F

D. S

Choose the most appropriate from the options given below:

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R:

Assertion A: $\mathrm{H}_2 \mathrm{Te}$ is more acidic than $\mathrm{H}_2 \mathrm{~S}$.

Reason R: Bond dissociation enthalpy of $\mathrm{H}_2 \mathrm{Te}$ is lower than $\mathrm{H}_2 \mathrm{~S}$.

In the light of the above statements, choose the most appropriate from the options given below:

Given below are two statements:

Statement - I: Along the period, the chemical reactivity of the elements gradually increases from group 1 to group 18 .

Statement - II: The nature of oxides formed by group 1 elements is basic while that of group 17 elements is acidic.

In the light of the above statements, choose the most appropriate from the options given below:

Match List I with List II.

Choose the correct answer from the options given below :

Given below are two statements:

Statement I : Fluorine has most negative electron gain enthalpy in its group.

Statement II : Oxygen has least negative electron gain enthalpy in its group.

In the light of the above statements, choose the most appropriate from the options given below

The element having the highest first ionization enthalpy is

Anomalous behavior of oxygen is due to its

Given below are two statements : one is labelled as Assertion $\mathbf{A}$ and the other is labelled as Reason $\mathbf{R}$ :

Assertion A : The first ionisation enthalpy decreases across a period.

Reason $\mathbf{R}$ : The increasing nuclear charge outweighs the shielding across the period.

In the light of the above statements, choose the most appropriate from the options given below :

Given below are two statements :

Statement I : The electronegativity of group 14 elements from $\mathrm{Si}$ to $\mathrm{Pb}$, gradually decreases.

Statement II : Group 14 contains non-metallic, metallic, as well as metalloid elements.

In the light of the above statements, choose the most appropriate from the options given below :

Given below are two statements :

Statement (I) : The $4 \mathrm{f}$ and $5 \mathrm{f}$ - series of elements are placed separately in the Periodic table to preserve the principle of classification.

Statement (II) : S-block elements can be found in pure form in nature.

In the light of the above statements, choose the most appropriate answer from the options given below :

Which of the following statements are not correct?

A. The electron gain enthalpy of $\mathrm{F}$ is more negative than that of $\mathrm{Cl}$.

B. Ionization enthalpy decreases in a group of periodic table.

C. The electronegativity of an atom depends upon the atoms bonded to it.

D. $\mathrm{Al}_{2} \mathrm{O}_{3}$ and $\mathrm{NO}$ are examples of amphoteric oxides.

Choose the most appropriate answer from the options given below :

For elements $\mathrm{B}, \mathrm{C}, \mathrm{N}, \mathrm{Li}, \mathrm{Be}, \mathrm{O}$ and $\mathrm{F}$, the correct order of first ionization enthalpy is

Given below are two statements: one is labelled as Assertion $\mathbf{A}$ and the other is labelled as Reason $\mathbf{R}$

Assertion A : The energy required to form $\mathrm{Mg}^{2+}$ from $\mathrm{Mg}$ is much higher than that required to produce $\mathrm{Mg}^+$

Reason $\mathbf{R}: \mathrm{Mg}^{2+}$ is small ion and carry more charge than $\mathrm{Mg}^{+}$

In the light of the above statements, choose the correct answer from the options given below.

The correct order of electronegativity for given elements is:

Which one of the following elements will remain as liquid inside pure boiling water?

Group-13 elements react with $\mathrm{O}_{2}$ in amorphous form to form oxides of type $\mathrm{M}_{2} \mathrm{O}_{3}~(\mathrm{M}=$ element). Which among the following is the most basic oxide?

The difference between electron gain enthalpies will be maximum between :

The correct increasing order of the ionic radii is

Match List I with List II

Choose the correct answer from the options given below :

Given below are two statements :

Statement I : The decrease in first ionization enthalpy from B to Al is much larger than that from Al to Ga.

Statement II : The d orbitals in Ga are completely filled.

In the light of the above statements, choose the most appropriate answer from the options given below

Inert gases have positive electron gain enthalpy. Its correct order is :

The first ionization enthalpy of Na, Mg and Si, respectively, are : 496, 737 and $786 \mathrm{~kJ} \mathrm{~mol}^{-1}$. The first ionization enthalpy ($\mathrm{kJ} \,\mathrm{mol}^{-1}$) of $\mathrm{Al}$ is :

In which of the following pairs, electron gain enthalpies of constituent elements are nearly the same or identical?

(A) Rb and Cs

(B) Na and K

(C) Ar and Kr

(D) I and At

Choose the correct answer from the options given below :

The incorrect statement is

Given two statements below :

Statement I : In $\mathrm{Cl}_{2}$ molecule the covalent radius is double of the atomic radius of chlorine.

Statement II : Radius of anionic species is always greater than their parent atomic radius.

Choose the most appropriate answer from options given below :

The first ionization enthalpies of Be, B, N and O follow the order

The IUPAC nomenclature of an element with electronic configuration [Rn] $5 \mathrm{f}^{14} 6 \mathrm{d}^{1} 7 \mathrm{s}^{2}$ is :

The correct order of electron gain enthalpy ($-$ ve value) is :

Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : The first ionization enthalpy for oxygen is lower than that of nitrogen.

Reason R : The four electrons in 2p orbitals of oxygen experience more electron-electron repulsion.

In the light of the above statements, choose the correct answer from the options given below.

Match List - I with List - II :

Choose the correct answer from the options given below :

Among the following, basic oxide is :

Element "E" belongs to the period 4 and group 16 of the periodic table. The valence shell electron configuration of the element, which is just above "E" in the group is

The correct order of increasing ionic radii is

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : The ionic radii of O^2$-$ and Mg²⁺ are same.

Reason (R) : Both O^2$-$ and Mg²⁺ are isoelectronic species.

In the light of the above statements, choose the correct answer from the options given below.

The correct order of electron gain enthalpies of Cl, F, Te and Po is

Given below are the oxides:

Na₂O, As₂O₃, N₂O, NO and Cl₂O₇

Number of amphoteric oxides is :