Brainscape's Knowledge GenomeTM

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


See full index

AS Chemistry > 1.7 - Simple Equilibria and Acid-Base Titrations > Flashcards

1.7 - Simple Equilibria and Acid-Base Titrations Flashcards

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

What is a reversible reaction?

A

One that can go in either direction depending on the conditions.

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

What is a dynamic equilibrium?

A

When the foward and reverse reactions occur at the same rate.

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

What is Le Chatelier’s principle?

A

If a system at equilibrium is subjected to a change then the position of equilibrium will shift to minimise that change.

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

What happens when the conc of a reactant is increased?

A

The position of equilibrium shifts to the right and more products are formed.

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

What does the pressure of a gas depend on?

A

The number of molecules in a given gas.
The greater the number of molecules, the greater the number of collisions per unit time, therefore the greater the pressure of gas.

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

What does high pressure mean on an equilibrium system?

A

high pressure = higher amount of moles on one side
Increasing the pressure moves the position of the equilibrium to whichever side of the equation has fewer gas molecules.

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

What is meant by ‘endothermic’?

A

Absorbing heat from surroundings (positive)

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

What is meant by ‘exothermic’?

A

Gives out heat to surroundings (negative)

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

What reaction is it if enthalpy change is positive?

A

The foward reaction is endothermic

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

What reaction is it if enthalpy change is negative?

A

The foward reaction is exothermic

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

What do catalysts do?

A

Speeds up a chemical reaction by lowering the activation energy of the reaction. Does not effect the position of the equilibrium, but equilibrium is reached faster.

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

How does a catalyst effect a reversible reaction?

A

A catalyst will increase the rate of the foward reaction and backward reaction to the same extent.

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

What is an equilibrium constant?

A

The position of equilibrium in a reversible reaction may be described in precise terms by combining the equilibrium concentrations to give a value.
GIven the symbol Kc (where c indicates ratio for concentration)

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

What is the equation for equilibrium constant?

A

aA + bB = cC + dD
Kc = (C)c(D)d/(A)a(B)b
Kc = products/reactants
Conc is raised to number of moles in equation.
Units should be moldm-3

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

What is an acid in terms of protons?

A

Acids are proton (H+) donors

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

What is a base in terms of protons?

A

Bases are proton (H+) acceptors

17
Q

What is the process of dissociating?

A

Acids donating H+ ions in an aqueous solution.

18
Q

Name 4 common acids.

A

Hydrochloric acid HCl
Sulphuric acid H2SO4
Nitric acid HNO3
Ethanoic acid CH3COOH

19
Q

Name 4 common bases.

A

Magnesium oxide MgO
Sodium hydroxide NaOH
Calcium oxide CaO
Ammonia NH3

20
Q

What is meant by a concentrated acid?

A

A concentrated acid consists of a large quantity of acid and a small quantity of water.

21
Q

What is meant by a dilute concentrated acid?

A

A dilute acid contains a large quantity of water and a small quantity of acid.

22
Q

How can you measure the acidity of a solution?

A

Measured by the concentration of aqueous hydrogen ions.

23
Q

What is the equation for pH?

A

pH = -log10 (H+)
(where H+ is concentration in mol dm-3)
(the negative sign is pH decreasing as H+ increases, if concentration is greater than 10-7 mol dm-3, the pH is less than 7)

24
Q

Where are acids on the pH scale?

A

0-6 red, orange, yellow

25
Q

What is considered neutral on the pH scale?

A

7 green

26
Q

Where are alkalis on the pH scale?

A

8-14 blue, dark blue, purple

27
Q

What are the 3 types of titrations?

A

Acid/base titration, back and double.

28
Q

What are the 3 key apparatus for a titration?

A

Burette, pipette and conical flask

29
Q

What counts as an accurate result for a titration?

A

At least 2 titres within 0.20cm^3 of eachother are required
Use titres within 0.20cm^3 for mean calculations.

30
Q

What is a back titration?

A

A back titration is where the concentration of an unknown compound is determined by reacting with a known amount of excess reagent.

31
Q

What is a double titration?

A

Finding out 2 unknown concentrations in a solution through use of 2 different indicators.

AS Chemistry (15 decks)

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