Periodic Trends

Question 1

does atomic radius increase or decrease going down a group

Answer 1

increase as the more you go down, the more electron shells there are and each electron shells is further away from the nuclues

Question 2

does atomic radius increase of decrease going left to right

Answer 2

Decrease: as it increases the nuclear charge - more protons results in higher positive charge and this increases attraction to the negative eletrons pulling them closer.

Question 3

what is ionisation energy

Answer 3

measures the minimum amount of energy needed to remove the single most loosely bound electron from an atom in the neutral gaseous state

Question 4

how does ionisation energy increase on a periodic table

Answer 4

left to right
- Due to the decreased atomic radius and increasing nuclear charge (+), the valence electrons (-) are attracted more strongly to the nucleus. Therefore more energy is needed to overcome this greater attraction.

down to up
- Due to electrons increased distance from the nucleus and a greater number of electron shells, the positive nuclear charge is shielded and has a lesser effect on the valence electrons. Therefore less energy is needed to overcome this attraction.

Question 5

what is electronegativity

Answer 5

ability of an atom in a molecule to attract electrons to itself

Question 6

how does electronegativity increase

Answer 6

left to right, electrons are negativiely charged and left to right increase amount of protons which increase positive charge and inrease force of attraction for electrons

up to down - decreases distance between protons and electrons in outer layer so the protons have a less positve nuclear charge effect on it, decreasing ability to attract electrons in outer layer