Topic 4 Inorganics

Question 1

Group 2 + water —> ?

Answer 1

Metal Hydroxide (base) + H2(g)

Question 2

Trend of reactivity in group 2

Answer 2

Increase

Question 3

Group 2 + O2—>?

Answer 3

Metal oxide (base)

Question 4

What is the appearance of a group 2 oxide

Answer 4

White solid

Question 5

Does group 2 hydroxide solubility increase or decrease down the group

Answer 5

Increase

Question 6

Solubility trend of group 2 sulfates

Answer 6

Decrease down the group

Question 7

What do group 2 Carbonates decompose to

Answer 7

Metal oxides and carbon dioxide

Question 8

What do group 2 nitrates decompose to

Answer 8

Metal oxides, nitrogen dioxide and oxygen

Question 9

How does carbonate/nitrate stability change as you go down group 2 and why

Answer 9

Increase - large electron cloud in anion is distorted - distorted anions can decompose more easily - size of cation increase down group, charge density decreases so less distortion of anion

Question 10

Are group 1 or 2 carbonated more thermally stable

Answer 10

Group 1

Question 11

Which is the only group group 1 carbonate to decompose under a Bunsen and what does it form

Answer 11

Lithium carbonate —-> lithium oxide and carbon dioxide

Question 12

What do group 1 nitrates decompose to

Answer 12

Group 1 Nitrites and oxygen

Question 13

What does LiNO3 decompose to

Answer 13

Li2O, NO2 and O2

Question 14

What are the formulas of nitrate and nitrite ions

Answer 14

NO3- and NO2-

Question 15

What are 2 method to test thermal stability of nitrates

Answer 15

Measure how long it takes to produce an amount of oxygen. Use a gas syringe or a glowing splint. Or measure how long it takes to produce NO2 (toxic brown gas)

Question 16

What is the method to test thermal stability of carbonates

Answer 16

Time to turn limewater cloudy (or use a gas syringe)

Question 17

How do you get different colours in flame tests

Answer 17

Electrons absorb energy from flame, move to higher energy subshells, when they drop back energy released as photons. Different colours depend on wavelength of energy released.

Question 18

Flame colour: Li

Answer 18

Crimson

Question 19

Flame colour sodium

Answer 19

Orange

Question 20

Flame colour potassium

Answer 20

Lilac

Question 21

Flame colour rubidium

Answer 21

Red

Question 22

Flame colour caesium

Answer 22

Blue

Question 23

Flame colour calcium

Answer 23

Brick red

Question 24

Flame colour Strontium

Answer 24

Crimson

Question 25

Flame colour Barium

Answer 25

Green

Question 26

Colour and state of group 7 elements

Answer 26

Fl2 - pale yellow gas Cl2 - pale green gas Br2 - brown - orange liquid I2 - grey solid

Question 27

What reaction occurs with halogens in cold alkali. Include equation

Answer 27

Disproportionation X2 + 2NaOH —-> NaXO + NaX + H2O

Question 28

What reaction occurs with halogens and HOT alkali give equation

Answer 28

Disproportionation 3X2 + 6NaOH —> NaXO3 + 5NaX + 3H2O

Question 29

How is bleach made

Answer 29

Disproportionation of sodium hydroxide and chlorine to make sodium chlorate (I)

Question 30

Three uses of bleach

Answer 30

-Treating water -Bleaching paper and fabrics -Cleaning agents

Question 31

How does adding water to chlorine sterilise the water

Answer 31

Chlorate ion is formed (ClO-) which kills bacteria

Question 32

What kind of agent are halide ions

Answer 32

Reducing - they lose an electron

Question 33

Does reducing power of Halide ions increase or decrease down the group

Answer 33

Increase

Question 34

What is the only possible set of product of sulfuric acid and chloride ions

Answer 34

NaHSO4 + HCl

Question 35

What are the 2 possible set of products of Br- and Na2SO4

Answer 35

NaHSO4 + HBr and SO2 + Br2 + 2H2O

Question 36

What are the 4 possible sets of products of I- and H2SO4

Answer 36

1. NaHSO4 + HI 2. SO2 + I2 + 2H2O 3. 3I2 + S + 4H2O 4. 4I2 + H2S +4H2O

Question 37

What is the standard state of hydrogen halides

Answer 37

Gas

Question 38

What forms when ammonia reacts with hydrogen halides and what is the visible observation

Answer 38

White fumes of ammonium halide

Question 39

Test and colours for halides

Answer 39

Nitric acid then silver nitrate, white Cl-, cream Br-, yellow I-

Question 40

How to confirm silver nitrate test for halides with ammonia

Answer 40

AgCl precipitate dissolve in dilute and conc ammonia, AgBr ppt dissolve only in conc ammonia AgI ppt is insoluble in ammonia

Question 41

Carbonate test and how to confirm

Answer 41

Acid then limewater

Question 42

Sulfate test

Answer 42

Barium Chloride after dilute HCl

Question 43

Test for ammonium ions

Answer 43

Add NaOH and heat - use damp red litmus paper to test - ammonia will dissolve and turn litmus paper blue

Question 44

Test for hydroxides

Answer 44

Turn red litmus paper blue