The Modern Periodic Table

The following metals are arranged in the increasing order of their metallic character. Choose the correct option.

Elements present in any group have the same number of

Identify the correct order of elements according to their metallic character.

Identify the correct order of elements according to their metallic character:

Elements with atomic numbers $7, 15, 33 \mathrm{and} 51$ belongs to same group in the periodic table. Because they have the same number of:

Which of the following has the maximum electronegativity?

An incorrect statement in regard to halogens is $\mathrm{HI}>\mathrm{HBr}>\mathrm{HCl}>\mathrm{HF}$

Consider the two elements below one labeled as assertion (a) and the other as Reason (R). Examine these two elements carefully and decide if Assertion (A) and Reason (R) are individually true if so (R) is a correct explanation of (A) select your answer using the code below:

Assertion (A): Magnesium imparts characteristic colour to the flame.

Reason (B): Due to the small size and high effective nuclear charge ionisation enthalpy of magnesium is high.

Which of the following elements exhibit variable valency?

Select the correct set of statements regarding change in properties, as we move from left ot right in the second period of periodic table.

(i) Atomic size decreases

(ii) Valency remains the same

(iii) Electronegativity increases

(iV) Metallic character decreases

Which atom has the smallest size?

Element M forms a chloride with the formula ${\mathrm{MCl}}_3$. Element M would most likely in the same group of periodic table as:

Which of the following element is more electropositive?

Element having highest electronegativity in the periodic table is

Which of the following is true about the two substances?

Statement- I: Ordinarily ${\mathrm{H}}_2\mathrm{S}$ is a gas and ${\mathrm{H}}_2\mathrm{O}$ liquid.

Statement- II: Sulphur is more electronegative so that it forms a hydrogen bond.

Atomic radius of chlorine is $99 \mathrm{pm}$. Distance between nuclei of its two atoms in molecule will be

Which of the following sets does not belong to a group in the periodic table?

${\mathrm{KO}}_2$ (potassium superoxide) is used in oxygen cylinders in space and submarines because it

How many groups are there in modern periodic table?

Read carefully the following statements regarding the ions ${\mathrm{Na}}^{+}, {\mathrm{Mg}}^{2+},{\mathrm{F}}^{-}\mathrm{and} {\mathrm{O}}^{2-}$.

(I) All ions have the same number of valence electrons.
(II) All ions belong to the elements of the same period of the periodic table.
(III) All ions have the same electronic configuration.
(IV) All ions have the same number of electron shells.