List of top Chemistry Questions on Classification of elements and periodicity in properties

Which of the following ions is the strongest oxidizing agent? (Atomic Number of Ce = 58, Eu = 63, Tb = 65, Lu = 71)

Which of the following elements has the highest electronegativity?

Electronegativity of chlorine is less than oxygen because:

Which of the following is the correct decreasing order of electronegativity?

Which of the following elements has the highest electronegativity?

In long form of periodic table an element 'X' is present in group 'Y' in which Mn is also an element. X, Y respectively are

Among Li, Na, O, S, the elements having the most negative electron gain enthalpy and least negative electron gain enthalpy respectively are:

Observe the following data (\(\Delta_i H_1\), \(\Delta_i H_2\) and \(\Delta_{eg}H\) represent the first, second ionisation enthalpies and electron gain enthalpy respectively).

Using the data identify the most reactive metal.

In Sr (Z=38), the number of electrons with \(l=0\) is x, number of electrons with \(l=2\) is y. \((x-y)\) is equal to (\(l\) = Azimuthal quantum number)

Match the following

The correct answer is

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

A metalloid is:

A pair of isoelectronic species having a bond order of one is:

Which of the following statements related to lanthanoids is incorrect?

Given below are two statements:
Statement I: The correct order of first ionization enthalpy values of Li, Na, F, and Cl is \( \text{Na} < \text{Li} < \text{Cl} < \text{F} \).
Statement II: The correct order of negative electron gain enthalpy values of Li, Na, F, and Cl is \( \text{Na} < \text{Li} < \text{F} < \text{Cl} \).
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:

The correct order of the first ionization enthalpy is

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 :

The element which shows only one oxidation state other than its elemental form is :

Consider the following elements.

Which of the following is/are true about A',B',C'andD' ? A. Order of atomic radii: \( B' < A' < D' < C' \)
B. Order of metallic character: \( B' < A' < D' < C' \)
C. Size of the element: \( D' < C' < B' < A' \)
D. Order of ionic radii: \( B^{+} < A^{+} < D^{+} < C^{+} \)
Choose the correct answer from the options given below: