T12 Acid-base equilibria Flashcards Preview

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Flashcards in T12 Acid-base equilibria Deck (43)
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1

acids

proton donors, releasing H + ions in water to form hydroxonium ions (H3O+)

2

bases

proton acceptors
take H+ ions from water molecules in solution to form OH- ions

3

strong acids /bases

dissociate completely in water
e.g HCl/ NaOH

4

weak acids/bases

dissociate partially in water
forms an equilibrium lying to the left

5

conjugate pairs

species linked by the transfer of a proton

6

conjugate base

species that has lost a proton

7

conjugate acid

species that has gained a proton

8

neutralisation reactions

when acids and base react together to form water and a salt.

9

neutral solution

equal conc of H+ and OH- ions

10

standard enthalpy change of neutralisation

enthalpy change when solutions of an acid and base react under standard conditions to produce one mole of water.
always negative as is exothermic

11

weak acid base neutralisation enthalpy

vary as only dissociate partially/reversibly and ions get used up quickly

12

strong acid base neutralisation enthalpy

no dissociation enthalpy just the reaction of H+ and OH- ions

13

pH equation

-log10(H+)

14

pH define

measure of hydrogen ion concentration

15

monoprotic acids

each mole of acid produces one mole of hydrogen ions

16

acid conc for strong, monoprotic acids

concentration of H+ ions

17

how do you find H+ conc from the pH

10 to the negative pH

18

polyprotic acids

acids with more than one proton available to release into solution.

19

how do you find pH of a weak acid

Ka

20

Ka

acid dissociation constant

21

Ka equation

(H+ conc * acid conc at eq)/conc of acid at start

22

Kc

equilibrium constant

23

Kw

ionic product of water

24

Kw equation

concentration of OH- * concentration of H+

25

what's Kw units

mol^2dm^-6

26

Kw of pure water

conc of H+ squared

27

Kw at 25 degrees celsius or 298 K

1*10^-14

28

pKw

-log10(Kw)

29

Kw from pKw

10^-pKw

30

pKa

-log10(Ka)