Brainscape's Knowledge GenomeTM

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


See full index

Sec 3 Chemistry > Acids, Bases and Salts 1 > Flashcards

Acids, Bases and Salts 1 Flashcards

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

Describe the solubility of the following ions.
1: NO3 ^-
2: SO4 ^2-
3: CO3 ^2-
4: O ^2-
5: OH ^-
6: PO4 ^3-
7: Cl ^-
8: Br ^-
9: I ^-
10: sodium salts
11: potassium salts
12: ammonium salts

A

1: All nitrates are soluble.
2: All sulfates are soluble except lead sulfate (Pb ^2+), barium sulfate (Ba ^2+), and calcium sulfate (Ca ^2+).
3: All carbonates are insoluble except Na+, K+ and NH4+.
4: All oxides are insoluble except Na+ and K+.
5: All hydroxides are insoluble except Na+ and K+. Ba ^2+ and Ca ^2+ are slightly soluble.
6: All phosphates are insoluble except Na+, K+ and NH4+.
7: All chlorides are soluble except Ag+ and Pb 2+.
8: All bromides are soluble except Ag+ and Pb 2+.
9: All iodides are soluble except Ag+ and Pb 2+.
10: All sodium salts are soluble.
11: All potassium salts are soluble.
12: All ammonium salts are soluble.

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

State the formula for ethanoic acid.

A

CH3COOH

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

State the ions produced in aqueous solution of the following acids:
1: hydrochloric acid
2: nitric acid
3: sulfuric acid
4: ethanoic acid

A

1: H+ (aq), Cl- (aq)
2: H+ (aq), NO3 ^- (aq)
3: H+ (aq), SO4 ^2- (aq)
4: H+ (aq), CH3COOH ^- (aq)

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

Define an acid.

A

An acid is a substance in which its molecules dissociate in water to produce hydrogen ions.

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

What factor is responsible for the properties of acids?

A

The presence of hydrogen ions.

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

Ammonia and ethanol are hydrogen-containing compounds. Why are they not acids?

A

They do not produce hydrogen ions when dissolved in water.

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

Define the basicity of an acid.

A

The number of ionisable hydrogen ions that can be produced by a molecule of the acid.

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

State the number of hydrogen ions that can be yielded when
1: a molecule of a monobasic acid is dissociated.
2: a molecule of a dibasic acid is dissociated.
3: a molecule of a tribasic acid is dissociated.

A

1: 1 H+ ion
2: 2 H+ ions
3: 3 H+ ions

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

Define the strength of an acid.

A

The extent of an acid’s dissociation in water.

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

Define a strong acid and a weak acid respectively.

A

A strong acid is one in which its molecules dissociate completely in water to produce a high concentration of hydrogen ions.
A weak acid is one in which its molecules dissociate partially in water to produce a low concentration of hydrogen ions.

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

Name two types of uses for the following acids.
1: H2SO4
3: HCl
5: CH3CO2H
Name one type of use for the following acids.
4: HNO3
5: H3PO4
6: H2CO3

A

1: fertiliser / car batteries / detergents
2: cleaning of metals / leather processing
3: vinegar / glue
4: fertiliser / explosives
5: fertiliser / food additives
6: soft drinks

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

State the difference between a dilute acid solution and a concentrated acid solution.

A

A dilute acid solution contains a small amount of dissolved acid per unit volume of water, while a concentrated acid solution contains a large amount of dissolved acid per unit volume of water.

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

What does pH measure?

A

pH measures the concentration of H+ ions in an aqueous solution of an acid.

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

State the formula of pH.

A

pH = -lg [H+], where H+ refers to the concentration of H+ ions in water

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

State the factors affecting pH of an acid solution.

A

Its strength, concentration and basicity.

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

List the general properties of an acid.

A

1: It has a sour taste.
2: It dissolves in water to form solutions that conduct electricity. / It is a good conductor of electricity in aqueous state.
3: It turns blue litmus paper red.
4: It has a pH value less than 7.
5: It is able to change the colour of indicators.

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

List the chemical properties of acids.

A

1: Acids react with metals to form salt and hydrogen gas.
2: Acids react with metal carbonates to form salt, carbon dioxide and water.
3: Acids react with bases to form salt and water in a neutralisation reaction.

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

Identify the unreactive metals.
calcium (Ca)
zinc (Zn)
copper (Cu)
tin (Sn)
silver (Ag)
gold (Au)
lead (Pb)
platinum (Pl)
aluminium (Al)
iron (Fe)

A

Cu, Ag, Au, Pl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Identify the metals that can be displaced from their oxide using carbon.
tin (Sn)
magnesium (Mg)
zinc (Zn)
gold (Au)
lead (Pb)
silver (Ag)
aluminium (Al)
copper (Cu)

A

Sn, Zn, Au, Pb, Ag, Cu

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

Complete the chemical reaction.
CuO (s) + H2 (g) -> ?

A

CuO (s) + H2 (g) -> Cu (s) + H2O (l)

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

Predict the observation when a magnesium ribbon is added to hydrochloric acid.

A

Brisk effervescence of colourless, odourless gas that extinguished a lighted splint is observed.

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

Define a salt.

A

A salt is the ionic compound formed when the hydrogen ions from an acid are displaced by metals or ammonium ions. The anion of salt comes from an acid.

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

Describe the test for hydrogen gas.

A

Place a lighted splint at the mouth of the reaction test tube. If the lighted splint extinguishes with a ‘pop’ sound, hydrogen gas is produced.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Predict the observation when calcium carbonate is added to hydrochloric acid.

A

Brisk effervescence of colourless, odourless gas that produced a white precipitate when bubbled into limewater is observed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Describe the test for carbon dioxide gas.

A

Bubble the gas through a test tube of limewater using a delivery tube. If a white precipitate is formed with limewater, carbon dioxide gas is produced.

26
Q

Describe the neutralisation reaction.

A

Neutralisation is the combination of hydrogen ions from an acid with hydroxide ions from an alkali or base to form water molecules and salt as the only products.

27
Q

State the general ionic equation for neutralisation between acids and alkali.

A

H+ (aq) + OH- (aq) -> H2O (l)

28
Q

The following statements about sulfuric acid are all correct.
1: A white precipitate is formed when aqueous barium chloride is added.
2: The solution turns anhydrous copper(II) sulfate from white to blue.
3: Addition of Universal Indicator shows that the solution has a pH value of less than 7.0.
4: The solution reacts with copper(II) oxide, forming a blue solution.

Which two statements confirm the acidic nature of the solution?

A

3 and 4

29
Q

Define a base.

A

A base is a substance that dissociates in water to produce hydroxide ions.

30
Q

Define an alkali

A

A base that is soluble in water.

31
Q

State the ions produced in aqueous ammonia.

A

NH4 ^+ (aq) and OH- (aq)

32
Q

Define a strong base and a weak base respectively.

A

A strong base is one in which its molecules dissociates completely in water to produce a high concentration of hydroxide ions. A weak base is one in which its molecules dissociates partially in water to produce a low concentration of hydroxide ions.

33
Q

Define the acidity of a base.

A

The number of ionisable hydroxide ions that can be produced by a formula unit of the base.

34
Q

List the general properties of alkalis.

A

1: Alkalis have a soapy and slippery feel.
2: Alkalis turn red litmus paper blue.
3: Alkalis taste bitter.
5: Alkalis have pH value more than 7.
6: Alkalis are good conductors of electricity.
7: Alkalis are able to change the colour of indicators.

35
Q

List the chemical properties of alkalis.

A

1: Alkalis react with acids to form salt and water in a neutralisation reaction.
2: Alkalis react with some metal ions to form insoluble metal hydroxides.
3: Alkalis react with ammonium salts to displace ammonia.

36
Q

With state symbols, write down the balanced equation when ammonia dissolves in water.

A

NH3 (g) + H2O -> <- NH4+ (aq) + OH- (aq)
- reversible arrows
- no such thing as ammonium hydroxide / oxide!

37
Q

State the general word equation when an alkali reacts with ammonium salt.

A

alkali + ammonium salt -> ammonia + water + salt

38
Q

Describe the test for ammonia gas.

A

If a colourless, pungent gas that turns damp red litmus paper blue is produced, ammonia gas is produced.

39
Q

Describe the precipitation reaction and state its function.

A

Precipitation reaction: Alkalis react with a salt solution to produce an insoluble metal hydroxide and a soluble metal salt.
Function: To identify cations, with the insoluble metal hydroxide precipitating out of the reaction mixture.

40
Q

Name two types of uses for the following bases.
1: ammonia solution
2: calcium oxide
3: magnesium hydroxide
4: sodium hydroxide

A

1: window cleaning / fertiliser
2: (quicklime) neutralising acidic soil / make iron and cement
3: toothpaste to neutralise acid on teeth / antacids to relieve indigestion
4: soaps / detergents

41
Q

Write an equation in terms of pH and pOH at 25°C.

A

pH + pOH = 14

42
Q

An aqueous solution contains 1.0 * 10^-5 mol dm^-3 of hydrochloric acid. Calculate the concentration of H+ in mol dm^-3, and hence the pH of this solution at 25°C.

A

HCl -> H+ (aq) + Cl- (aq)
[H+] = [HCl] = 1.0 * 10^-5 mol dm^-3 (answer)
pH = -lg [H+] = -lg (1.0 * 10^-5) = 5.00 (answer)

43
Q

An aqueous solution contains 0.10 mol dm^-3 of calcium hydroxide (a strong base). Calculate the concentration of OH- in mol dm^-3, and hence the pH of this solution at 25°C.

A

Ca(OH)2 (aq) -> Ca 2+ (aq) + 2OH- (aq)
[OH-] = 2 * [Ca(OH)2] = 0.200 mol dm^-3 (answer)
pOH = -lg [OH-] = -lg 0.2 = 0.699
pH = 14 - pOH = 14 - 0.699 = 13.3 (answer)

44
Q

State 3 indicators to determine the pH of a solution.

A

Universal Indicator, phenolphthalein, methyl orange

45
Q

Describe how the colour of a Universal Indicator changes from pH 0 to 14.

A

from 0 to 2: red
from 3 to 4: orange
from 5 to 6: yellow
from 7 to 8: green
from 9 to 11: blue
from 12 to 14: violet / purple

46
Q

State the colour changes of methyl orange and phenolphthalein respectively when the solution turns from acidic to neutral to alkaline.

A

methyl orange: red to orange to yellow
phenolphthalein: colourless to pale pink to pink

47
Q

Define an oxide.

A

An oxide is a compound of oxygen and another element.

48
Q

List all the types of oxides.

A

Acidic, basic, amphoteric and neutral oxides.

49
Q

What constitutes an acidic oxide?

A

Oxygen and a non-metal

50
Q

State the property of acidic oxides.

A

Acidic oxides react with alkalis to form a salt and water.

51
Q

What constitutes a basic oxide?

A

Oxygen and a metal

52
Q

State 2 properties of basic oxides.

A

1: Basic oxides are solids at room temperature.
2: Basic oxides react with acids to form a salt and water.

53
Q

What are amphoteric oxides?

A

Amphoteric oxides are metallic oxides that react with both acids and bases to form salts and water.

54
Q

List 3 examples of amphoteric oxides.

A

Zinc oxide (ZnO), aluminium oxide (Al2O3), lead(II) oxide (PbO)
Acronym: ZAP

55
Q

Name the salt and its formula when sodium hydroxide reacts with the following oxides.
1: aluminium oxide
2; lead(II) oxide
3: zinc oxide

A

1: sodium aluminate, NaAl(OH)4
2: sodium plumbate, Na2Pb(OH)4
3: sodium zincate, Na2Zn(OH)4

56
Q

State 2 properties of neutral oxides.

A

1: Neutral oxides show neither basic nor acidic properties.
2: Neutral oxides are insoluble in water.

57
Q

List 3 examples of neutral oxides.

A

water (H2O), carbon monoxide (CO), nitric oxide (NO)

58
Q

Which pair of substances shows no observable change when mixed together?
1: zinc oxide + sodium hydroxide
2: copper hydroxide + hydrogen chloride
3: magnesium oxide+ sodium hydroxide
4: phosphorus pentoxide (P4O10) + water

A

Option 3
Bases do not react with alkali.

59
Q

Cake mixtures contain a solid mixture of tartaric acid and sodium hydrogen carbonate among other ingredients. Why will the mixture only “rise” if water is added?

A

The dough will rise when carbon dioxide gas is produced when HCO3-(aq) reacts with H+(aq) from tartaric acid to produce CO2 and H2O. In the absence of H2O, tartaric acid will not ionise to produce H+ ions and no CO2 will be produced.

60
Q

A farmer attempts to correct the pH of the soil in his field by using solid calcium hydroxide, then adding ammonium nitrate (a fertiliser) to improve soil fertility. What is your opinion on his procedures?

A

Ammonium nitrate should not be added straight after the soil is treated with solid calcium hydroxide as these two compounds would react, with the loss of ammonia gas. The effectiveness of the fertiliser will be much reduced.

Sec 3 Chemistry (15 decks)

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