M3S1 – Periodicity

An example of a p-block element is:

An element which is a solid at room temperature consisting of molecules is:

An element which consists of a giant structure of atoms held together by covalent bonding is:

In the periodic table a periodic pattern is:

In which of these pairs do both entities have the same electron configuration?

(i) Li and Na

(ii) Na⁺ and Mg²⁺

(iii) F^- and Cl^-

(iv) Cl^- and Ar

In the periodic table the elements are arranged in order of:

(i) atomic number

(ii) mass number

(iii) number of protons in the nucleus

(iv) number of protons and neutrons in the nucleus.

Which of these true statements help to explain why the values of the first ionisation enthalpies (energies) of the group 1 metals fall down the group from lithium to caesium?

(i) Down the group, the outer electron gets further from the nucleus

(ii) The charge on the nucleus increases down the group

(iii) Greater shielding means that the attraction between the nucleus and the outer electron reduces down the group

(iv) In all the atoms the outer electron is an s-electron

Which of these statements about atomic and ionic radii are true?

(i) Atomic radii increase down group 2

(ii) Ionic radii increase down group 7

(iii) Atomic radii decrease across period 3

(iv) In period 3 the ionic radii are smaller than the atomic radii

Across period 2 from lithium to neon, the first ionisation enthalpy (energy) of:

(i) oxygen is higher than that of neon

(ii) oxygen is higher than that of nitrogen

(iii) boron is higher than that of beryllium

(iv) beryllium is higher than that of lithium

Across period 3 from sodium to argon:

(i) the metal with the lowest melting point is sodium

(ii) the element with the highest melting point is silicon

(iii) the non-metal with the lowest melting point is argon

(iv) the melting points of all the non-metals are lower than those of the metals