Brainscape's Knowledge GenomeTM

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


See full index

Chemistry > Module 5 > Flashcards

Module 5 Flashcards

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

Reversible reactions

A

forward and reverse reactions are possible- drawn with a arrow pointing in both directions

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

What are the properties of reversible reactions?

A
  • reverse thermodynamic properties

- values of enthalpy, entropy and gibbs free energy would be the negative or the reverse

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

What are the types of equilibrium a reaction can have?

A

Dynamic equilibrium and static equilibrium

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

Are all reversible reactions in dynamic equilibrium

A

No. Dynamic equilibrium is only`a type of reversible reaction

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

Investigation- reversibility of cobalt(II) chloride hexahydrate
What materials are involved in this experiment?

A
  • 5g of cobalt (II) chloride hexahydrate
  • Evaporating dish
  • Gauze mat
  • Bunsen burner
  • Demineralised water
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Investigation- reversibility of cobalt(II) chloride hexahydrate
What is the method of the experiment? Draw experimental set-up.

A
  1. Add 5g of cobalt(II) chloride hexahydrate in an evaporating dish and set it is on top of a gauze mat
  2. Gently heat the cobalt (II) chloride hexahydrate with Bunsen burner and observe for any colour changes
  3. When there are no colour changes after 5 minutes, add 5 mL of demineralised water to re-dissolve the salt
  4. Evaporate the solution and observe for changes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Investigation- reversibility of cobalt (II) chloride hexahydrate
Why was demineralised water added to the salt after evaporation?

A

By adding water to the evaporated solution, we test the reversibility of cobalt(II) chloride hexahydrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Investigation- reversibility of cobalt (II) chloride hexahydrate
Observations are?

A
  1. Cobalt (II) chloride hexahydrate is a dark pink colour
  2. Heating cobalt (II) chloride hexahydrate causes the substance to turn into a purple colour (cobalt (II) chloride dihydrate)
  3. Heating cobalt (II) chloride dihydrate causes it to become sky blue (cobalt (II) chloride anhydrous)
  4. The colour of cobalt(II) chloride dihydrate is a fleeting colour where it quickly appears and disappears
  5. By adding water, the solution becomes dark pink
  6. When reheating the solution, the observations are recalled to be the same
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the colour of cobalt (II) chloride hexahydrate?

A

Pink

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

What s the colour of cobalt chloride dihydrate?

A

Purple

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

What form of cobalt (II) chloride is sky blue?

A

Anhydrous

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

What happens when hexahydrate is heated?

A

The waters of crystallisation are gradually vaporised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Investigation of the reversibility of cobalt (II) chloride hexahydrate
Why does the appearance of the solution remain the same despite the form of cobalt(II) chloride.

A

Despite the water crystallisation number, as cobalt (II) chloride is dissolved the hydration spheres formed around them is exactly the same- the number of crystallisation numbers don’t have an effect.

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

Investigating the reversibility of the combustion of metals-

Materials?

A
  • magnesium strip
  • steel wool
  • crucible and lid
  • bunsen burner
  • tripod and pipeclay triangle
  • test tube
  • Ice bath
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Investigating the reversibility of the combustion of metals- Method . Draw a diagram.

A
  1. Place pipeclay triangle above tripod( with the heat proof mat underneath)
  2. Place bunsen burner underneath the tripod
  3. Place crucible on top of pipeclay triangle with the lid slightly opened
  4. Place magnesium strp within the crucible
  5. Ignite flame on bunsen burner and open gas pipe
  6. Observe any changes to the magnesium strip
  7. Collect remaining solid and place within a test tube in an ice bath
  8. Observe any changes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Investigating the reversibility of the combustion of metals

What colour of the solid formed by heating the magnesium in the crucible?

A

White solid- magnesium oxide

Red solid- iron (III) oxide

17
Q

Investigating the reversibility of the combustion of metals- Why is the white solid placed in the ice bath?

A

By placing it in an ice bath, we test the reversibility by attempting to reverse the original change of heating it.

18
Q

Investigating the reversibility of the combustion of metals- What colour is formed when steel wool is heated?

A

Reddish brown solid is formed as steel wool is heated.

19
Q

What is dynamic equilibrium?

A

The rates of conversion in the forwards reaction- reactants to products- and the reverse reaction- products to reactants- are equal and non-zero

20
Q

What is static equilibrium

A

The rates of forward and reverse reactions are equal and practically zero. The reaction doesn’t proceed after equilibrium has been reached.
mainly due to high activation energies

21
Q

The movement of particles in the dynamic and static equilibrium.

A

Dynamic equilibrium

  • movement of particles in the forward and reverse reactions
  • constant microscopic flux
  • no macroscopic observations
22
Q

Static equilibrium- properties

A

Static

  • No movement of particles in the forward and reverse reactions
  • No microscopic flux
  • No macroscopic observations
23
Q

Dynamic equilibrium- reaction rate

A
  • Rate of reaction depends on concentration of the reactants
  • forward reaction is initially fast as the concentration of reactants is large at first
  • slow reverse reaction rate
  • As the reactants are consumed within the reaction and the concentration of the products increase, the forward rate of reaction rate decreases and the reverse rate of reaction decreases
  • Dynamic equilibrium is reached when the reverse rate of reaction equals the forward rate of reaction
24
Q

Concentration of dynamic and static equilibrium

A

Dynamic and Static equilibrium have constant concentrations

25
Q

System

A

A whole composed of both substance and energy. Anything outside of the system is known to be the surroundings

26
Q

Closed systems

A
  • constant number of particles
  • energy can be transferred with the surroundings
  • matter cant enter the system
27
Q

Do static and dynamic equilibriums require closed systems?

A

Yes

28
Q

Open system

A

The system can exchange both matter and energy

Chemistry (2 decks)

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