Periodicity - Trends

Question 1

Define first ionisation energy

Answer 1

The energy required to remove an electron from a neutral atom in the gaseous state

Question 2

Define electronegativity

Answer 2

The tendency of an atom to attract and form bonds with electrons

Question 3

Define reactivity

Answer 3

How easily an atom gains or loses electrons

Question 4

Explain the horizontal and vertical trends of first ionisation energy

Answer 4

Increases across period - Valence shell stability and electron shielding, elements on the left/right do not/want electrons to stabilise

Decreases down group - As atomic radii increase, the attraction from the nucleus is weaker and therefore, easier to remove electrons

Question 5

Explain the horizontal and vertical trends of electronegativity

Answer 5

Increases across period - Valence shell stability and electron shielding, elements on the left/right do not/want electrons to stabilise

Decreases down group - As atomic radii increase, the attraction from the nucleus is weaker and therefore, harder to attract electrons

Question 6

Explain the horizontal and vertical trends of reactivity (with water) for metals

Answer 6

Decreases across period - Valence shell stability and electron shielding, elements have more electrons and further from stability

Increases down group - As atomic radii increase, the attraction from the nucleus is weaker and therefore, easier to remove electrons

Question 7

Explain the horizontal and vertical trends of atomic radii

Answer 7

Decreases across period - Electron shielding occurs and the nucleus is more attractive while more electron shells are not added

Increases down groups - Electron shell is added

Question 8

Explain the horizontal and vertical trends of metallic nature

Answer 8

Decreases across period - As metallic nature is how readily an atom loses an electron, valence electron stability and electron shielding

Increases down group - As atomic radii increase, the attraction from the nucleus is weaker and therefore, easier to remove electrons

Question 9

Explain the horizontal and vertical trends of boiling point

Answer 9

Increase then decrease across period - Intermolecular forces impacts boiling points and begins to decrease at semi-metals

None

Question 10

Explain the horizontal and vertical trends of melting point

Answer 10

Increase then decrease across period - Intermolecular forces impacts boiling points and begins to decrease at semi-metals

None

Question 11

Explain the horizontal and vertical trends of reactivity (with water) for non-metals

Answer 11

Increases across period - Valence shell stability, and electron shielding, elements have more electrons and closer to stability

Decreases down group

Question 12

Define metallic nature

Answer 12

How readily an element loses an electron