L3 Trends across the periodic table

Question 1

How does atomic radius change down a group?

Accepted Answer

increases

Question 2

The power or tendency of an atom to draw electrons towards itself in a covalent bond is called..

Accepted Answer

electronegativity

Question 3

What is the definition of the first electron affinity?

Accepted Answer

Energy released when 1 mole of electrons ADDS to 1 mole of gaseous atoms

Question 4

Why does the ionic radius decrease down a group?

Accepted Answer

more shielding, less nuclear attraction on outer shell

Question 5

What is the definition of first ionization energy?

Accepted Answer

Energy needed to remove 1 mole of electrons from 1 mole of Gaseous atoms

Question 6

Why are the 2nd,3rd etc electron affinities always endothermic?

Accepted Answer

negative ion repels extra electron

Question 7

Why does the atomic radius decrease across a period?

Accepted Answer

Same shielding, more nuclear attraction on outer shell, more protons

Question 8

Write the equation for the first ionization energy of potassium

Accepted Answer

K(g) - e- ==> K+(g)

Question 9

Write the equation for the first electron affinity of potassium

Accepted Answer

K(g) + e- ==> K+(g)

Question 10

Why does why does aluminium have a lower ionization energy than expected?

Accepted Answer

electron is in a new 3p shell so more shielding

Question 11

Why does atomic radius increase down a group?

Accepted Answer

More shielding, less nuclear attraction on outer shell

Question 12

Why does sulfur have a lower Ionisation Energy than expected?

Accepted Answer

3p electrons have to pair up so repusion

Question 13

How does the ionic radius change down a group?

Accepted Answer

increases

Question 14

Why is the first electron affinity always exothermic?

Accepted Answer

More energy is released than absorbed

Question 15

Why does the ionic radius decrease across a period for ions?

Accepted Answer

Same shielding, more nuclear attraction on outer shell, more protons

Question 16

How does the atomic radius change across a period?

Accepted Answer

decreases

Question 17

Write the equation for the first ionization energy of oxygen

Accepted Answer

O(g) - e- ==> O+(g)

Question 18

What does SNAP stand for?

Accepted Answer

Shielding, Nuclear attraction on outer electrons, Atomic radius, Protons

Question 19

How does the ionic radius change across a period for ions?

Accepted Answer

decreases

Question 20

Write the equation for the first electron affinity of sulfur

Accepted Answer

S(g) + e- ==> S+ (g)

Questions 20