Chemistry 9701 · AS & A Level · The Periodic Table: chemical periodicity

The Periodic Table: chemical periodicity — practice question

The elements in the third period display periodicity in both their chemical and physical properties.
(a)

The graph below shows the atomic and ionic radii across the third period.

(a(i))[2]

Explain why atomic radius decreases across the third period.

(a(ii))[1]

Explain why, from sodium to silicon, the ionic radii are smaller than the atomic radii.

(a(iii))[2]

Explain why, for phosphorus to chlorine, the ionic radii are greater than the atomic radii.

(b)

The first ionisation energies of the elements across the third period show an overall rise. Aluminium and sulfur do not fit this overall pattern.

(b(i))[2]

Explain why aluminium has a lower first ionisation energy than magnesium.

(b(ii))[2]

Explain why sulfur has a lower first ionisation energy than phosphorus.

(c)

The elements in the third period, from sodium to silicon, can react with chlorine to make chlorides.

(c(i))[3]

State and explain the pattern of change of oxidation number that occurs to both chlorine and the different Period 3 elements when they react together.

(c(ii))[2]

Give the equations that show the reactions of sodium chloride and silicon(IV) chloride when each is added separately to water.

(c(iii))[2]

Complete the table to describe the structure and bonding in sodium chloride and silicon(IV) chloride.

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