Chemistry Unit 1

Question 1

define ionisation energy

Answer 1

energy required to remove 1 mole of electrons from 1 mole of gaseous atoms

Question 2

what is the shielding effect

Answer 2

effect of inner electrons which reduces the pull of the nucleus on electrons in the outer shell (higher shielding effect=lower ionisation energy)

Question 3

are nitrates soluble

Answer 3

yes all nitrates are soluble

Question 4

are group 1 carbonates and sulfates soluble

Answer 4

yes

Question 5

are group 2 halides soluble

Answer 5

yes, all are soluble

Question 6

what colour is the precipitate produced when lead reacts with iodine (PbI2)

Answer 6

yellow

Question 7

is Mg(OH)2 soluble

Answer 7

no

Question 8

is MgSO4 soluble

Answer 8

yes

Question 9

is Ba(OH)2 soluble

Answer 9

yes

Question 10

hydroxide solubility __________ down Group 2

Answer 10

increases

Question 11

carbonate solubility __________ down Group 2

Answer 11

decreases

Question 12

sulfate solubility __________ down Group 2

Answer 12

decreases

Question 13

define electronegativity

Answer 13

the ability of an element to attract and hold a boding pair of electrons

Question 14

as you go across a period electronegativity ________ because the number of protons increase

Answer 14

increases

Question 15

as you go down a group electronegativity ________ because the bonding electrons are further from the nucleus (more shielding)

Answer 15

decreases

Question 16

metals of group 2 all react by _______ 2 electrons (________) to form positive ions. this ________ the other reactant

Answer 16

losing
oxidation
reduces

Question 17

what is formed when group 2 metals react with oxygen

Answer 17

metal oxide

Question 18

what is formed when group 2 metals react with water

Answer 18

basic metal hydroxides

Question 19

what flame test colour when lithium is burned

Answer 19

red

Question 20

what flame test colour when sodium is burned

Answer 20

golden yellow

Question 21

what flame test colour when potassium is burned

Answer 21

lilac

Question 22

what flame test colour when calcium is burned

Answer 22

brick red

Question 23

what flame test colour when strontium is burned

Answer 23

crimson

Question 24

what flame test colour when barium is burned

Answer 24

apple green

Question 25

what flame test colour when magnesium is burned

Answer 25

no colour

Question 26

what flame test colour when copper is burned

Answer 26

blue/green

Question 27

trend in reactivity of s-block (group 1 and 2) metals

Answer 27

reactivity increases as you go down the group

Question 28

the melting point (volatility) __________ as you go down group 7 because the molecules get __________ and so _______ electrons can move around and set up __________________ dipoles

Answer 28

increases
larger
more
temporary

Question 29

why is Fe3+ a good oxidising agent

Answer 29

Fe3+ is very electronegative and outer electrons are less shielded so it can easily attract an electron and form Fe2+

Question 30

how to test for chloride ions

Answer 30

add silver ions in dilute nitric acid, if positive reaction then a white precipitate that dissolves in dilute Ammonia (aq) will form

Question 31

how to test for bromide ions

Answer 31

add silver ions in dilute nitric acid, if positive reaction then a cream precipitate that dissolves in concentrated Ammonia (aq) will form

Question 32

how to test for iodide ions

Answer 32

add silver ions in dilute nitric acid, if positive reaction then a yellow precipitate that does not dissolve in concentrated Ammonia will form

Question 33

is Ca(OH)2 soluble

Answer 33

no, only sparingly soluble

Question 34

is CaSO4 soluble

Answer 34

no, only sparingly soluble

Question 35

is CaCO3 soluble

Answer 35

no

Question 36

is PbI2 soluble

Answer 36

no

Question 37

is BaSO4 soluble

Answer 37

no

Question 38

is BaCO3 soluble

Answer 38

no