Brainscape's Knowledge GenomeTM

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


See full index

Chemistry > Acids and Alkalis > Flashcards

Acids and Alkalis Flashcards

1
Q

PH

A

a measure of how alkaline or acidic a substance is
0-14
low numbers = acid, high numbers = alkaline

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

ways of measuring pH

A

Universal indicator
ph probe with meter
phenolphalien
methyl orange

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

base

A

any substance with a PH greater than 7

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

alkali

A

subgroup of bases that are soluble in water
forms OH- ions in water

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

acid

A

any substance that forms an aqueous solution with a PH less than 7
forms H+ ions in water

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

common acids

A

Hcl (hydrochloric acid)
H2SO4 (sulfuric acid)
HNO3 (nitric acid)

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

titration

A

a technique where a solution of known concentration is used to determine the concentration of an unknown solution

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

general equations for a neutralision reaction

A

metal oxide + acid –> salt + water (this is for an acid)
metal hydroxide + acid –> salt + water

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

ionic equation for neutralisation reaction

A

e.g. H+ + OH- –> H2O
e.g. HCl + NaOH –> NaCl + H2O
if a substance is neutral, it will have a PH of 7

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

ionic equation definition

A

reaction involving ions in a solution
anything that is made up of ions and is aqueous will break up into its ions in a solution

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

spectator ions

A

ions that do not contribute in the equation

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

how titration works

A

use a pipette and add some acid to a flask.

add a small amount of phenolphthalein indicator.

fill the burette with base and carefully drop some into the acid

when the colour changes, stop and record the volume

repeat several times and get an average.

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

how can you make the titration test easier

A

we can add acid to the base slowly and take readings on a PH probe (gives exact PH values)
we can plot a graph against volume of acid added

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

how can you make the titration test easier

A

we can add acid to the base slowly and take readings on a PH probe (gives exact PH values)
we can plot a graph against the volume of acid added

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

equivalence point

A

point in titration at which the volume of acid added is just enough to neutralize the solution

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

strong acids

A

dissociate completely
PH of 0-2
can have low concentrations

17
Q

weak acid

A

dissociate partially
PH of 3-6
can have high concentrations

18
Q

examples of weak acids

A

ethnoic acid, citric acid

19
Q

acid concentration

A

the mass of acid dissolved in a given volume of water
changing the concentration of an acid affects its PH

20
Q

equation for concentration

A

concentration = mass/volume

21
Q

dont confuse strength of an acid with concentration

A

just dont

22
Q

if an acid with a PH of 6 changes to a PH of 3, how much did the concentration change?

A

the H+ concentration has increased by a factor of 1000

23
Q

if an acid with a PH of 6 changes to a PH of 9, how much did the concentration change?

A

the H+ concentration has decreased by a factor of 1000

24
Q

other general equations that you have to know for the test

A

acid + metal –> salt + hydrogen
acid + metal carbonate –> salt + water + carbon dioxide

25
Q

all polyatomic ions to know

A

CO3^2-
Cl-
NO3-
SO4^2-

26
Q

precipitation reaction

A

adding two soluble salts together to make insoluble salts

27
Q

soluble or insoluble:
salts of Na, K and NH4
nitrates
common chlorides
common sulphates
common carbonates and hydroxides

A

soluble or insoluble:
soluble
soluble
soluble except silver and lead
soluble except lead, barium and calcium
insoluble except sodium, potassium and ammonium

28
Q

Acid strength

A

The amount of acid that dissociated (what portion of acid molecules ionised in water)

29
Q

colour of methyl orange in acid

A

red

30
Q

colour of methyl orange in alkali

A

yellow

31
Q

colour of phenolphelien in acid

A

colourless

32
Q

colour of phenolphthalein in alkali

A

pink

33
Q

explain the steps in a soluble salt from insoluble base experiment

A

pour a dilute acid into a flask

heat flask

add base, e.g. copper oxide into the flask
heat speeds up the rate of reaction

repeat last step until base stops reacting with acid
this is done to ensure the mixture has reacted completely

leave to cool

filter mixture into a beaker and pour into an evaporating basin

place evap basin on top of a beaker with water, the beaker with water will evaporate which will in turn heat the evap basin

heat until small amount of mixture in the evap basin is left
this is done as too much evaporation would leave behind a powder. we want salt crystals

leave to cool, soon after, crystals will form

Chemistry (13 decks)

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