Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

chemistry > module 6 HSC > Flashcards

module 6 HSC Flashcards

(69 cards)

Start Studying
1
Q

properties of acids

A
  • sour taste
  • burn skin
  • blue litmus to red
  • pH < 7
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

properties of bases

A
  • bitter taste
  • soapy feel in aqueous solution
  • red litmus to blue
  • pH > 7
  • caustic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

acid + base

A

salt + water

HNO3 + NaOH –> H2O + NaNO3

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

acid+ carbonate

A

salt + water + carbon dioxide

2HCl (aq) + Na2CO3 (s) –> CO2 (g) + H2O (l) + 2NaCl(aq)

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

acid + active metal

A

salt + hydrogen gas

H2SO4 (aq) + Ba(s) –> H2 (g) + BaSO4(s)

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

what are indicators

A

substances which change colour based on the pH of the environment
- methyl orange (orange)
- bromthymol blue (green)
- phenolphthalein (pink)

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

methyl orange

A

3.1 - 4.4

red - orange - yellow

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

bromothymol blue

A

6.0 - 7.6
yellow - green - blue

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

phenolphthalein

A

8.3 - 10.0
colourless - pale pink - pink/magenta

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

natural indicator

A

red cabbage

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

antoine lavoiser

A

acids contain O
bases neutralise acids

a: raised the need to define acids and bases
d: statement is wrong eg. HCl

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

humphrey davy

A

Acids contain replaceable H. Bases neutralise acids.

a: worked for many acids
d: cannot explain acidic or basic oxides

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

arrhenius

A

acids release H+ in solution and bases release OH - in solution
a:
- works for many acids and bases
- explains the common mechanism of acid base neutralisations

d:
- does not recognise solvents in determining the acidic/weakness of acid
- cannot explain basic nature of carbonates, acidic or basic salts in not aqueous form

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

bronsted lowry

A

acids donate protons, bases accept protons

a:
- recognises role of solvent in determining the strength and weakness of an acid
- explains acidic and basic behaviour in non aqueous solvents
- explains how species can be amphiprotic
- recognises conjugate acids and bases

d:
- cant explain amphoteric substances
- cannot explain acids or bases that dont accept/donate protons

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

amphoteric substances

A

can act as both an acid or base

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

amphiprotic

A

can act as either an acid or base in different chemical environments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

enthalpy of neutralisation

A

thermal energy change

q = mcat
delta h = -q/n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

proticity + what is a protic substance

A

capacity to act as a proton donor
eg. mono HCl, diprotic H2SO4, triprotic H3PO4

  • strong is the first (one directional arrow) , weak is the scond (biodirectinal arrow)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

degree of ionisation

A

how much it ionises
strong acid: fully ionises 100%
weak acid: does not fully ionise <100%

[A-]eq / [HA] initial x 100%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

strong acid degree of ionisation

A

100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

weak acid degree of ionisation

A

<100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

strong acids

A

HCl, HBr, HI, HNO3, H2SO4 (first is strong, second is weak)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

strong bases

A

HF, CH3COOH, H2CO3, H3PO4, C6H8O7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

conjugate of base HSO2-

A

acid H2SO4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
conjugate of acid HCl
base Cl-
25
conjugate of strong ...
extremely weak/almost neutral
26
conjugate of weak ...
weak
27
conjugate of extremely weak ...
strong
28
prove that HCO3 from NaCO3 is amphiprotic
strong base : ... strong acid: ...
29
neutralisation
acid base reaction that goes to completion and does not directly produce H3O+ and OH- - strong goes to completion - weak does not go to completion explain with both le chateliers and bronsted lowry eg. CH3COOH weak acid in water - NaOH strong base in water CH3Cooh + NaOH -> NaCh3CH3COOH + H2O - since acetic acid is a weak acid relative to water but strong acid relative to sodium hydroxide and sodium hydroxide is a strong base relative to water and acetic acid is stronger than water --> the acetic acid will ionise completely in the presence of sodium hydroxide where neutralisation is complete
30
changing degree of ionisation
depends on concentration acids however only temperature changes the Ka
31
pH
-log10[H3O+]
32
[H3O+]
10^-pH
33
factors that affect an acids pH
1. concentration 2. strength 3. proticity (strong acids) 4. degree of ionisation (weak acids)
34
concentration impacts on pH
more concentrated acid = lower pH think about how a log is an inverse
35
strength impact on pH
strong acids have a lower pH as it completely ionises in water
36
proticity impact on pH
strong acids only higher proticity = lower pH sulfuric acid has a lower pH than HCl as it has both a strong first ionisation and weak second ionisation
37
degree of ionisation impact on pH
weak acids only high degree of ionisation = lower pH citric < acetic < carbonic - although carbonic acid has more protons readily available to donate, it has a much lower degree of ionisation
38
what salt does strong acid + strong base produce
neutral salt
39
what salt does strong base + weak acid produce
acidic salt
40
what salt does strong acid + weak base produce
basic salt
41
what salt does weak acid + weak base produce
any of them..?
42
what is the levelling effect of a solvent
acid: strength of acid is levelled/limited by the ability of a solvent to accept protons base: strength of base is levelled by the ability of solvent to donate protons
43
define titration
volumetric analysis which the concentration of a solution is determined by measuring the volumes of solutions involved in a reaction - uses neutralisation reactions
44
equivalence point
point at which equal moles of H3O+ ions and OH- ions have been reacted together
45
endpoint
the point at which a sustained colour change is achieved using an appropriate indicator
46
titration error
the difference between the equivalence point and the endpoint
47
titre
the minimum volume required to reach the endpoint of the neutralisation reaction in the titration
48
titrant
solution which is used to determine the concentration of an unknown solution
49
analyte
solution whose concentration is to be determined
50
standard solution
solution with known concentration
51
qualities looked for in a standard solution (primary standard) + example
- high purity - stability in air -high molecular weight - inexpensive and readily obtained eg. acid: hydrated oxalic acid (weak acid for strong base) base: anhydrous sodium carbonate (Na2CO3) / sodium hydrogen carbonate (NAHCO3) -> weak base for strong acid
52
what to avoid in a primary standard
weak acid and weak base together deliquescent compounds: absorb water from surrounding environment by reacting with CO2 in air which dissolves in the solution eg. NaOH + KOH hydroscopic: attract water molecules due to the presence of hydrophilic groups eg. H2SO4
53
what is al the glassware rinsed with
all glassware rinsed with demineralised water first pipette + burette = rinsed finally with solution they are to contain to ensure the concentration of substances they are to contain are accurate (the demin water would dilute the solution) volumetric flask + conical flask = rinsed thoroughly with demineralised water so the number of moles of the substance can be accurate
54
beaker
used to dissolve the dry powdered primary standard to make the standard solution
55
volumetric flask
cleaned with demin and and filled to the gradation line with the standard solution then inverted 20 times to homogenise the solution
56
FIX TITRATION FLASH CARDS
57
neutralisation real life applications
antacid tablets: - antacid tablets contain Mg(OH)2/Al(OH)3 that undergo neutralisation with excess gastric acid in the human stomach eg HCl tooth decay: - acids from food and drinks cause tooth decay - toothpaste is weakly alkaline with undergoes neutralisation with acids present on the cavity - CaCO3 baking: - sodium bicarbonate (NaHCO3) (s) - reacts with acids - gives cake airy quality and produces CO2 to help rise industrial: - sodium hydrogen carbonate is used to neutralise any spills that are acidic.basic that is corrosive and causes harm to the environment and should e cheap, safe and weakly acidic/basic wastewater: treatment of waste water - HF used to neutralise NaOH and Ca(OH)2 and produces a solid that can be removed
58
antacid tablets
- antacid tablets contain Mg(OH)2/Al(OH)3 that undergo neutralisation with excess gastric acid in the human stomach eg HCl
59
baking
- sodium bicarbonate (NaHCO3) (s) - reacts with acids - gives cake airy quality and produces CO2 to help rise
60
tooth decay
- acids from food and drinks cause tooth decay - toothpaste is weakly alkaline with undergoes neutralisation with acids present on the cavity - CaCO3
61
industrial
- sodium hydrogen carbonate is used to neutralise any spills that are acidic/basic that is corrosive and causes harm to the environment and should e cheap, safe and weakly acidic/basic
62
waste water
treatment of waste water - HF used to neutralise NaOH and Ca(OH)2 and produces a solid that can be removed
63
styrofoam cup experiment
- imperfect insulator = heat loss ot the environment -> use styrofoam lid - thermometer should not touch the bottom of the cup as the reading will be wrong
64
Kw
10^-14 = Ka x Kb
65
pH + pOH
14
66
define a buffer
similar/comparable concentrations of a weak acid/base and its conjugate which resists the change in pH if another acid/base is added
67
how do buffers work
eg. carbonic acid (wa) is mixed with sodium hydrogen carbonate H2CO3/HCO3- system - then write the equations showing the addition of H3O+ and addition of OH- addition of H3O+: acid - acid consumed by HCO3- shifting the equation to the left to reduce [H3O+] by LCP - minimal change in [H3O+] , pH remains stable addition of OH-: base - base consumed and shifts left to decrease [OH-] by LCP then link back to buffer: therefore since the solution minimises changes in [OH-] and [H3O+], it can act as a buffer
68
example of buffers
human blood: - to maintain homeostasis acidic through exercise as more carbonic acid is produced: - shifts left to increase H2CO3 basic though hyperventilation: - ocean buffer: HCO3-/CO32- buffer system - shells and limestone composed of CaCO3 that dissolve into CO32-

chemistry (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions