chapter 3

Question 1

how are elements in the periodic table arranged?

Answer 1

in order of increasing atomic number

Question 2

what is metallic structure

Answer 2

a lattice of positive ions in a sea of delocalised electrons

Question 3

what happens to ionisation energy down a group

Answer 3

ionisation energy decreases

Question 4

properties of metallic elements

Answer 4

large atomic radii, low ionisation energy, less exothermic electron affinity and low electronegativity

Question 5

what are electrons in the outer shell known as?

Answer 5

valence electrons

Question 6

how is the periodic table divided

Answer 6

in to blocks (s,p,d,f,g)

Question 7

what is atomic radius?

Answer 7

used to describe the size of an atom

Question 8

what happens to atomic radius down a group?

Answer 8

it increases

Question 9

what happens to atomic radius across a period?

Answer 9

decreases

Question 10

what is ionic radius?

Answer 10

a measure of the size of an ion

Question 11

what happens to ionisation energy down a group?

Answer 11

decreases

Question 12

why does ionisation energy decrease down a group?

Answer 12

because the valence electron is further away from the nucleus and therefore less strongly attached

Question 13

what happens to ionisation energy across a period?

Answer 13

increases

Question 14

why does ionisation energy increase across a period?

Answer 14

increase in nuclear charge across the period

Question 15

what is electron affinity

Answer 15

enthalpy change when one electron is added to each atom in one mole of gaseous atoms

Question 16

what happens to electron affinity down a group?

Answer 16

decreases

Question 17

what happens to electron affinity across a period

Answer 17

becomes more exothermic

Question 18

why does electron affinity become more exothermic across a period

Answer 18

an increase in nuclear charge and a decrease in atomic radius from left to right

Question 19

what is electronegativity?

Answer 19

a measure of the attraction of an atom in a molecule for the electron pair in the covalent bond

Question 20

what happens to electronegativity down a group

Answer 20

decreases

Question 21

what happens to electronegativity across a period?

Answer 21

increases

Question 22

why does electronegativity decrease down a group

Answer 22

the size of the atom increases so the bonding pair is further away from the nucleus

Question 23

why does electronegativity increase across a period

Answer 23

increase in nuclear charge across a period with no change in shielding

Question 24

what are group 1 elements known as?

Answer 24

alkali metals

Question 25

what are properties of alkali metals?

Answer 25

highly reactive, soft, low melting point

Question 26

what happens to melting point down group 1

Answer 26

decreases

Question 27

what determines the reaction of an element?

Answer 27

the number of valence elevctrons

Question 28

how do group 1 elements react with oxygen?

Answer 28

react vigorously with oxygen and tarnish rapidly in the air

Question 29

how do group 1 elements react with water?

Answer 29

react rapidly with water forming a metal hydroxide

Question 30

what are group 17 elements known as

Answer 30

halogens

Question 31

what happens to the melting point going down group 17

Answer 31

melting point increases

Question 32

why does melting point increase down group 17

Answer 32

london forces between molecules increase therefore more energy must be supplied to separate the molecules

Question 33

what does a amphoteric oxide react with

Answer 33

acids and bases

Question 34

what can oxides be classified as?

Answer 34

basic, acidic, amphoteric