Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

D.Chem 4- Inorganic + PT > Group 1 + Group 2 > Flashcards

Group 1 + Group 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

Trend in atomic radius

A

Group 2 elements form 2+ ions
Atomic radius increases down group 2 due to more shells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Trend in ionisation energy

A

-1st ionisation energy decreases down group
- down group more shells = more shielding= weaker attraction between nucleus and outer electrons
- electrons are further from nucleus = weaker attraction
- these factors outweigh increase in nuclear charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Group 2 + water forms what

A

Bases/ metal hydroxide
Sr(OH)2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Trends in reactivity down group 2

A
  • increases down the group
    Atom gets larger = electron further from nucleus and easier to remove
  • Be does not react
  • Mg only reacts slowly
  • reaction is much faster with steam
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Group 2 + oxygen = ?
What would you see

A

= metal oxides/ bases
Group 2 oxides = white solids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Group 2 oxides + water
What would form
What would happen to the PH

A
  • metal oxides react with H20 = form metal hydroxides = dissociate to form OH- ions = makes solution alkaline/base

Down the group solution will be more alkaline = hydroxides more soluble down group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Trends in solubility of hydroxides and sulphates of group 1 and 2

A
  • hydroxides get more soluble down group
  • sulphates get less soluble down group
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Group 2 oxides or hydroxides + Acids= ?

A

Base + acid = water
Neutralisation reaction
MgO + H2SO4 = MgSO4 + H2O

Sr(OH)2 + H2SO4 = SrSO4 + 2H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the rule about anion solubility?

A

1- if a anion has a double charge = solubility decreases down group

2- if anion has a single charge = solubility increases down group

Eg: hydroxides and sulfates have opposite solubility down group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Group 2 carbonate decomposition = ?

A

Carbonate = metal oxides + CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Group 2 nitrates decomposition = ?

A

Nitrates = metal oxide + nitrogen dioxide + oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Trend in thermal stability of carbonates and Nitrates down group 2

A

Carbonates and nitrates become more thermally stable down group

  • carbonate/nitrate ion has a large electron , can be distorted by positive group 2 ions
  • all G2 ions have 2+ charge but down G2 atom size gets larger = lower charge density
  • doesn’t distort the electron cloud as much
  • the less distortion the more stable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Are group 1 compounds more or less thermally stable than G2 compounds

A

More stable
- lower charge density due to only 1+ ion
- generally G1 compounds are stable under Bunsen burner except Lithium compounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

G1 carbonate decomposition = ?

A

Metal oxide and CO2
Only Li2CO3 decomposes under flame
Li acts as though it’s a group 2 due to very high charge density

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

G1 Nitrate decomposition = ?

A

Nitrites + oxygen
MNO2 + O2

Except Lithium Nitrate forms = lithium oxide + Nitrogen dioxide + oxygen

Nitrate = NO3-
Nitrite = NO2-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Name a way to measure thermal stability of nitrates

A
  • measure how long it takes to produce amount of oxygen with gas syringe
  • Time taken to produce amount of NO2 = a brown gas easily observed
17
Q

Make a way to measure thermal stability of carbonates

A

Time to taken to produce amount of CO2
- turns limewater cloudy

18
Q

What happens inside of a flame test

A
  • electrons move to a higher energy level as they absorb energy
  • when electrons drop down to lower levels = energy light released
  • different colours produced as different energy levels determine a wave lengths of light released
19
Q

Describe a flame test procedure

A

1- dip Nichrome wire into HCl
2- dip into sample
3- place loop into blue flame + observe

20
Q

What colour would be observed of the flame test of lithium

A

Crimson/Red

21
Q

What colour would be observed of the flame test of sodium

A

Yellow

22
Q

What colour would be observed of the flame test of potassium

A

Lilac

23
Q

What colour would be observed of the flame test of calcium

A

Dark Red / Yellowy Red

24
Q

What colour would be observed of the flame test of strontium

A

Crimson / Red

25
Q

What colour would be observed of the flame test of barium

A

Green

26
Q

What colour would be observed of the flame test of rubidium

A

Reddish purple

27
Q

What colour would be observed of the flame test of magnesium

A

Bright white but may be no change in colour of flame

28
Q

What colour would be observed of the flame test of caesium

A

Blue

29
Q

Trends in melting point down group 1 and 2

A

Melting point decreases down group
- Positive nucleus is further away from delocalised electrons
-More shells = more electron shielding

30
Q

Magnesium + steam =
Why does mg have different reactions

A

MgO + H2
-Very strong bonds between outer electrons and positive nucleus
-Least reactive group 2 element

31
Q

Can magnesium react with Cold water

A

No
Not reactive enough but can react with warm water

32
Q

Magnesium + warm water

A

= Mg(OH)2 + H2
A hydroxide and hydrogen
- hydrogen gas always forms in a group 2 reaction

33
Q

Why would you observe less white precipitate down group 2 when forming hydroxides

A
  • down group 2 solubility of hydroxides increases
  • less precipitate as it has dissolved more
34
Q

Group 2 oxide + acid

A

= salt and water
Eg: MgCl2 + H2O

35
Q

Is magnesium hydroxide solvable in water

A

No

36
Q

What is magnesium hydroxide used for

A
  • milk of magnesia
  • used to neutralise stomach acid
  • safe as it’s barely alkaline due to insoluabilty
37
Q

Why can Group 2 Hydroxides, Oxides and carbonates neutralise dilute acids

A

slightly basic

Magnesium Hydroxide = Milk of Magnesia = can neutralise stomach acid

38
Q

In terms of Solubility what are all Group 1 hydroxides

A

Soluble

whereas group 2 solubility increases down group

D.Chem 4- Inorganic + PT (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions