12. Acids and Bases Flashcards Preview

AQA A Level Physical Chemistry > 12. Acids and Bases > Flashcards

Flashcards in 12. Acids and Bases Deck (147)
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1

What is a Bronsted-Lowry acid?

A proton donor

2

What is a Bronsted-Lowry base?

A proton acceptor

3

When can protons only be given up by acids?

When there is a base that accept them

4

What do reactions between acids and bases involve?

Proton transfer

5

Where do most common acid-base reactions take place?

In aqueous solution

6

How are acids and bases generally defined? Why is this?

By the way they react with water - as most acid-base reactions take place in aqueous solution

7

What does how strong an acid/base is depend on?

How much they dissociate in water

8

How much do strong acids dissociate in water?

Almost completely dissociate

9

What is another phrase for 'dissociates'?

Ionises

10

General equation for strong acids/bases dissociating in water?

HA ⇋ H⁺ + A⁻

11

How much do weak acids dissociate in water?

Only slightly dissociate

12

Example of a strong acid dissociating in water?

HCl ⇋ H⁺ + Cl⁻

13

Example of a strong base dissociating in water?

NaOH ⇋ Na⁺ + OH⁻

14

Example of a weak acid dissociating in water?

CH₃COOH ⇋ CH₃COO⁻ + H⁺

15

Example of a weak base dissociating in water?

NH₃ + H₂O ⇋ NH₄⁺ + OH⁻

16

Is the strength of an acid/base different to its concentration?

Yes

17

What does the acidity of a solution depend on?

The concentration of H⁺ (aq) ions

18

What is pH defined as?

-log₁₀[H⁺]

19

What type of scale is the pH scale? Why is this?

Logarithmic, as the concentration of hydrogen ions in aqueous solution covers a wide range

20

When there is a smaller pH, what will be true of the concentration of H⁺ ions?

Higher concentration of H⁺

21

What types of acid are there?

• monoprotic

• diprotic

22

What is a monoprotic acid?

One that releases one H⁺ ion per molecule

23

What is a diprotic acid?

One that releases two H⁺ ions per molecule

24

Is HCl monoprotic or diprotic?

Monoprotic

25

Is H₂SO₄ monoprotic or diprotic?

Diprotic

26

In strong acids, what is the moles of a monoprotic acid equal to? Why?

The moles of H⁺, therefore [H⁺] = conc. of acid, because strong acids fully dissociate

27

In strong diprotic acids, what are the moles of H⁺ equal to?

Double the moles of acid, therefore [H⁺] = double conc. of acid

28

What effect do diprotic acids have on pH compared to monoprotic?

Results in lower pH (stronger acid)

29

How many decimal places is pH given to?

2

30

How can pH be used to calculate the concentration of H⁺?

[H⁺] = 10⁻ᵖᴴ