Chemistry Classification of Elements and Periodicity in Properties

Identify the element for which electronic configuration in +3 oxidation state is [Ar]3d⁵.

Consider the elements Mg, Al, S, P and Si, the correct increasing order of their first ionization enthalpy is:

For the reaction $2A?B+C,K_C=4*10^{-3}$ . At a given time, the composition of reaction mixture is: $\left[A\right]=\left[B\right]=\left[C\right]=2*10^{-3}M$ . Then, which of the following is correct?

Which of the following elements is considered as a metalloid?

Outermost electronic configuration of a group 13 element, E, is 4s², 4p¹. The electronic configuration of an element of p-block period-five placed diagonally to element, E is:

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

Assertion (A) : Metallic character decreases and non-metallic character increases on moving from left to right in a period.

Reason (R) : It is due to increase in ionization enthalpy and decrease in electron gain enthalpy, when one moves from left to right in a period.

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

A₃B₂ is sparingly soluble salt of molar mass M (g mol^-1) and solubility x g L^-1. The solubility prduct satisfies K_sp = $a{\left(\frac{x}{M}\right)}^5$ . The value of a is________. (Integer answer)

The pair, in which ions are isoelectronic with Al³⁺ is:

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

Given below are two statement: one is labeled as Assertion (A) and the other is labeled as Reason (R)

Assertion (A) : The ionic radii of O²⁺ and Mg²⁺ are same

Reason (R) : Both O²⁺ and Mg²⁺ are isoelectronic species

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