Group 7 & Redox

Question 1

Fluorine f2

Answer 1

Yellow gas

Question 2

Chlorine Cl2

Answer 2

Green gas

Question 3

Bromine Br2

Answer 3

Orange liquid

• often used in solution in water
• easily forms orange vapour

Question 4

Iodine i2

Answer 4

Grey crystalline solid

• often used in a (sort of) solution in water
• easily forms purple vapour

Question 5

Atomic radius down group

Answer 5

• increases

- more shells of electrons so bigger atom

Question 6

Electronegativity down group

Answer 6

• decreases
• more shells/ shielding
• so weaker attraction between nucleus + pair of electrons in covalent bond

Question 7

Electronegativity definition

Answer 7

Power of an atom to attract the 2 electrons in the covalent bond

Question 8

Melting and boiling points down group

Answer 8

• increases
• due to stronger van der Waals forces between molecules
• due to molecules having more electrons

Question 9

Ionisation energy down group 7

Answer 9

• decreases
• more shells/ shielding
• atoms get bigger
• so weaker attraction between nucleus + outer electron

Question 10

What is broken when states are changed?

Answer 10

Van der Waals forces not covalent bonds

Question 11

Halides

Answer 11

Fluoride
Chloride
Bromide
Iodide

Question 12

Halides charge?

Answer 12

• 1

Question 13

Halogens and halides reaction table

Answer 13

F- Cl- Br- I-
F2    X.  Y.   Y.  Y 
Cl2.  X.  X.  Y.  Y
Br2.  X.  X.  X. Y
I2      X.  X. X.  X

Question 14

What happens in halogen and halide reaction?

Answer 14

The halogen steals electron from the halide

Question 15

What happens when Bromide and Chlorine react?

Answer 15

Yellow solution

Question 16

What happens when iodide and chlorine react?

Answer 16

Brown solution

Question 17

What happens when iodide and bromine react?

Answer 17

Brown solution

Question 18

Halide and halogen overall reaction equation?

Answer 18

Halogen + 2 halide -> 2 new halide + new halogen
E.g Cl2 + 2I- -> 2 Cl- + I2
Use 2 to balance

Question 19

Oxidising power of halogens explainaiton

Answer 19

• halogen atom gains an electron when it oxidises the halide ion
• the small the halogen atom, the earlier it is to gain an electron as it is smaller and has less shielding

Question 20

Oxidising power strongest - weakest

Answer 20

Chlorine
Bromide
Iodine

Question 21

Oxidation states definition

Answer 21

A number representing how many electrons have either been lost or gained

Question 22

Oxidation number/ state of a single element

Answer 22

0

Question 23

Oxidation state of oxygen

Answer 23

-2

Question 24

Writing half equations steps

Answer 24

1) calculate oxidation states
2) balance equation
3) sort out electrons
4) for every O gained/lost, add/remove H2O
5) for every H gained/lost, ass remove one H+
6) check if total electric charge on left equals that in right

Question 25

Combining half equations

Answer 25

Put two equations together then balance | Should be no electrons in final equation

Question 26

Strongest to weakest reducing power of halogens

Answer 26

Iodide I- Bromide Br- Chloride Cl- Fluoride F-

Question 27

Reducing power of halogens explanations

Answer 27

- halide ion loses ion when it reduces the H2SO4 (sulfuric acid) - bigger halide ion, easier to lose electron because not shielding

Question 28

What does HCL produce?

Answer 28

Steamy fumes

Question 29

What acid is involved in reducing power of halides?

Answer 29

Concentrated sulfuric acid (H2SO4)

Question 30

Does chlorine want to gain or lose electron?

Answer 30

Gain

Question 31

Where are electrons on reduction?

Answer 31

Left

Question 32

Where are electrons in oxidation?

Answer 32

Right

Question 33

What is chlorine used for?

Answer 33

- swimming pools - water - kills bacteria

Question 34

What is H2SO4?

Answer 34

Sulfuric acid

Question 35

What is NAOH?

Answer 35

Sodium hydroxide

Question 36

What is NaCl?

Answer 36

Sodium chloride - table salt - roads

Question 37

What is NaClO?

Answer 37

Sodium chlorate | -bleach

Question 38

Most to learn soluble ions (H2SO4)

Answer 38

Mg 2+ (mgso4) Ca 2+ (caso4) Sr 2+ (srso4) Ba 2+ (baso4)

Question 39

Which H2SO4 ions are liquids?

Answer 39

MgSO4 | CaSO4

Question 40

Which H2SO4 ions are solids/white precipitates?

Answer 40

SrSO4 | BaSO4

Question 41

What is BaSO4 used for?

Answer 41

X-rays to light up insides as it is insoluble

Question 42

What are the 4 hydroxide ions? (NaOH)

Answer 42

Mg(OH)2 Ca (OH)2 Sr (OH)2 Ba (OH)2

Question 43

Which hydroxide ions are solids?

Answer 43

Mg (OH)2 | Ca (OH)2

Question 44

Which hydroxide ions are liquids?

Answer 44

Sr (OH)2 | Ba (OH)2

Question 45

What is the ammonia gas test?

Answer 45

- red litmus paper - damp - turns blue to detect ammonia

Question 46

What is NH4OH?

Answer 46

Ammonium hydroxide

Question 47

What are the 4 silver nitrate ions? (AgNO3)

Answer 47

AgF AgCl AgBr AgI

Question 48

What AgNO3 ions are solids?

Answer 48

AgCl AgBr AgI

Question 49

What AgNO3 ion is a liquid?

Answer 49

AgF

Question 50

What does AgF look like?

Answer 50

Colourless solution

Question 51

What does AgCl look like?

Answer 51

White precipitate

Question 52

What does AgBr look like?

Answer 52

Cream precipitate

Question 53

What does AgI look like?

Answer 53

Yellow precipitate

Question 54

What happens when AgCl/ AgF / AgI reacts with dilute NH3?

Answer 54

Nothing

Question 55

What happens when AgCl reacts with NH3?

Answer 55

Dissolve (colourless solution)

Question 56

What is NH3?

Answer 56

Ammonia

Question 57

What happens when AgI/ AgF reacts with concentrated NH3?

Answer 57

Nothinf

Question 58

Why don’t we react AgCl with concentrated NH3?

Answer 58

Because it already dissolved with dilute NH3

Question 59

What happens with AgBr reacts with concentrated NH3?

Answer 59

Dissolve (colourless solution)

Question 60

What is a text for hydroxide?

Answer 60

Add magnesium + vice versa

Question 61

What can be used to check for Br-?

Answer 61

Dilute NH3

Question 62

What can be used to text for Barium?

Answer 62

Sulfate (vice versa)

Question 63

What contains H+ ions?

Answer 63

Acid