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Chemistry > Acids, Bases and Salts > Flashcards

Acids, Bases and Salts Flashcards

1
Q

What is an acid?

A

An acid is a compound which when dissolved in water yields hydronium ion [H3O+] as the only positively charged ions

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2
Q

Give the equation representing addition of an acid to water, and formation of hydronium cation

A

HCl (aq) ⇌ H+ + Cl-; H+ + H2O ⇌ H3O+

HCl + H2O ⇌ H3O+ + Cl-

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3
Q

What is a base?

A

A base is a compound which reacts with hydronium ions of an acid to give salt and water only

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4
Q

Give an equation representing reaction of a base with a hydronium ion of an acid

A

CuO + 2HCl -> CuCl2 + H2O

Cu(OH)2 + H2SO4 -> CuSO4 + 2H2O

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5
Q

What is an alkali?

A

An alkali is a compound which when dissolved in water yields hydroxyl ions [OH-] as the only negatively charges ions

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6
Q

Give an equation representing the reaction of an alkali with water

A

NaOH [aq] ⇌ Na+ + OH- [Hydroxyl or hydroxide ion]

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7
Q

Is an alkali a base or an acid?

A

An alkali is a soluble base (in water)

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8
Q

Give examples of soluble bases (alkalis)

A

KOH, NaOH [strong alkalis], Ca (OH)2, NH4OH [weak alkalis], LiOH

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9
Q

Give an example of a strong alkali

A

NaOH

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10
Q

Give an example of a weak alkali

A

NH4OH

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11
Q

What are organic acids?

A

Acids derived from plants

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12
Q

Give examples of organic acids

A

Citric, oxalic, tartaric, acetic acid

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13
Q

What is an inorganic acid?

A

Acids derived from minerals [mineral acids]

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14
Q

Give examples of inorganic acids

A

HCl, H2SO4, HNO3

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15
Q

Name two acids on basis of source of acids

A
  1. Organic

2. Inorganic

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16
Q

Name two acids on basis of molecular composition

A
  1. Hydracids

2. Oxyacids

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17
Q

What are hydracids?

A

Acids containing hydrogen and a non-metallic element other than oxygen

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18
Q

Give examples of hydracids

A

HCl, HBr, HI

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19
Q

What are oxyacids?

A

Acids containing hydrogen, another element and oxygen

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20
Q

Give examples of oxyacids

A

HNO3, H2SO4

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21
Q

What does the strength of an acid depend on?

A

It depends on the concentration of hydronium ions present in an aqueous solution of an acid

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22
Q

What does the strength of an alkali depend on?

A

On the concentration of hydroxyl ions present in an aqueous solution of the alkali

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23
Q

What is a strong acid?

A

An acids which dissociates almost completely in aqueous solution thereby producing a high concentration of hydrogen [H+ ions] [or H3O+] ions

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24
Q

What does a strong acid contain?

A

Almost only ions

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25
Q

Give two equations representing the dissociation of a strong acid

A

HNO3 + H2O ⇌ H3O+ + NO3-

H2SO4 + 2H2O ⇌ 2H3O+ + SO4 2-

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26
Q

What is a strong alkali?

A

It is an alkali which dissociates almost completely in aqueous solution thereby producing a high concentration of hydroxyl [OH-] ions

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27
Q

What does a strong alkali consist of?

A

Almost only ions (contains solute molecules in addition to water molecules)

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28
Q

Give two equations representing the dissociation of a strong alkali

A

NaOH [aq] ⇌ Na+ + OH-

KOH [aq] ⇌ K+ + OH-

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29
Q

Give examples of strong acids

A

Hydrochloric, Sulphuric and Nitric acid

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30
Q

Give examples of strong alkalis

A

Lithium, Sodium, Potassium hydroxide

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31
Q

What is a weak acid?

A

It an acid which dissociates only partially in aqueous solution thereby producing a low concentration of hydrogen [H+] ions [or H3O+ ions]

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32
Q

What is a weak alkali?

A

It is an alkali which dissociates only partially in aqueous solution thereby producing a low concentration of hydroxyl [OH-] ions

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33
Q

Give an equation representing the dissociation of a weak acid

A

CH3COOH ⇌ CH3COO- + H+

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34
Q

Give an equation representing the dissociation of a weak alkali

A

NH4OH [aq] ⇌ NH4+ + OH-

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35
Q

What does a weak acid consist of?

A

Molecules and ions

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36
Q

What does a weak alkali consist of?

A

Molecules and ions

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37
Q

Give examples of weak acids

A

Acetic, citric, carbonic, formic acid

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38
Q

Give examples of weak alkalis

A

Ammonium hydroxide and Calcium hydroxide

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39
Q

How are crystals of glacial acetic acid formed?

A

On cooling of anhydrous acetic acid

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40
Q

What is a concentrated acid?

A

It is an acid having a relatively high percentage of acid in its aqueous solution

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41
Q

What is a concentrated alkali?

A

It is an alkali having a relatively high percentage of alkali in its aq. solution

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42
Q

What is a dilute acid?

A

It is an acid having a relatively low percentage of acid in its aqueous solution

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43
Q

What is the concentration of acid in a dilute acid?

A

Less than 1 mole/litre

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44
Q

What is a dilute alkali?

A

It is an alkali having a relatively low percentage of alkali in its aq. solution

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45
Q

What is the concentration of alkali in a dilute alkali?

A

Less than 1 mole/litre

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46
Q

What is the basicity of acids?

A

The no. of hydrogen ions [H+] which can be produced per molecule of the acid in aq. soln. or the no. of hydroxyl ions with which one molecule of an acid combines

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47
Q

What is a monobasic acid?

A

It ionizes in aq. soln. to produce one hydrogen ion per molecule of the acid. Or contains one replaceable hydrogen ion per molecule of the acid

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48
Q

In how many steps do monobasic acids dissociate in aq. soln.?

A

In one step

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49
Q

Name the salts monobasic acids form

A

They form only one type of salt [normal salt]

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50
Q

Give examples of monobasic acids

A

HCl, HNO3, CH3COOH

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51
Q

How many hydrogen atoms does acetic acid have?

A

4, but it ionizes in aq. soln. to produce one hydrogen ion per molecule of the acid

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52
Q

What is a dibasic acid?

A

It ionizes in aq. soln. to produce two hydrogen ions per molecule of the acid. Or contains two replaceable hydrogen ions per molecule of the acid

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53
Q

In how many steps do dibasic acids dissociate?

A

Two steps

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54
Q

Name the types of salts dibasic acids form

A

2 types - acid and normal salt

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55
Q

Give examples of dibasic acids

A

H2SO3, H2SO4, H2CO3

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56
Q

What is a tribasic acid?

A

It ionizes in aq. soln. to produce three hydrogen ions per molecule of the acid. Or contains three replaceable hydrogen ions per molecule of the acid

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57
Q

In how many steps do tribasic acids dissociate?

A

Three steps

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58
Q

Name the types of salts tribasic acids form

A

Three salts - two acid, one normal - have three replaceable hydrogen atoms

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59
Q

Name a normal salt

A

Trisodium phosphate

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60
Q

What is the acidity of bases?

A

The no. of hydroxyl ions [OH-] which can be produced per molecule of the base in aq. soln. or the no. of hydrogen ions with which a molecule of a base combines

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61
Q

What is a monoacidic base?

A

It ionizes in aq. soln. to produce one hydroxyl ion per molecule of the base or contains one replaceable hydroxyl ion per molecule of the base [if water soluble]

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62
Q

In how many steps does a monoacidic base dissociate?

A

In one step

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63
Q

Give examples of monoacidic bases

A

NaOH, KOH, NH4OH

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64
Q

What is a diacidic base?

A

It ionizes in aq. soln. to produce two hydroxyl ions per molecule of the base or contains two replaceable hydroxyl ions per molecule of the base [if water soluble]

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65
Q

In how many steps does a diacidic base dissociate?

A

One step

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66
Q

Give examples of diacidic bases

A

Ca(OH)2, Zn(OH)2, Cu(OH)2

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67
Q

What is a triacidic base?

A

It ionizes in aq. soln. to produce three hydroxyl ions per molecule of the base or contains three replaceable hydroxyl ions per molecule of the base [if water soluble]

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68
Q

In how many steps does a triacidic base dissociate?

A

One step

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69
Q

Give examples of triacidic bases

A

Al(OH)3, Fe(OH)3 [water insoluble]

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70
Q

What is the Arrhenius theory?

A

Acids are substances which dissociate in aqueous solution to give H+ ions. Strong acids dissociate almost completely, while weak acids dissociate partially

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71
Q

What is Lowry-Bronsted’s theory?

A

Acids are proton donors. Bases are proton acceptors

]proton = H+].

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72
Q

How does water exhibit charge separation?

A

The H atom of water carries a slight positive charge and the O atom, a slight negative charge

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73
Q

How many lone pairs of electrons does oxygen atom have in water?

A

Oxygen atom has two lone pairs of electrons not shared with any other atom

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74
Q

How does the formation of H3O+ ion come about from acid in aq. soln.?

A
  1. A proton (H+ ion) released from HCl adds on to the lone pair of electrons of oxygen atom of water molecule.
  2. The H1+ ion accepts the lone pair of electrons forming a coordinate covalent bond
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75
Q

Why does the H+ proton released from HCl add on to the lone pair of electrons of the oxygen atom of the water molecule?

A

Oxygen atom in H2O has a slight negative charge

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76
Q

What is a coordinate covalent bond?

A

The bond formed between the atom of a polar covalent molecule with lone pair of electrons and an ion which accepts the lone pair of electrons

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77
Q

How does the formation of OH- ion come about from alkalis in aq. soln.?

A
  1. A proton (H+ ion) released from water adds on the lone pair of electrons of the nitrogen atom of the ammonia molecule
  2. The H+ ion accepts the lone pair of electrons forming a coordinate covalent bond
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78
Q

How many lone pairs of electron does nitrogen in ammonia have?

A

1 lone pair

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79
Q

Why does the H+ ion released from water add on to the lone pair of electrons of the nitrogen atom of ammonia molecule?

A

Nitrogen atom of ammonia molecule has a slight negative charge

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80
Q

Name the ways acids are prepared

A
  1. From Non-Metals
  2. From Acidic Oxides
  3. From Salts
  4. By oxidation of non-metals
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81
Q

How are acids prepared from non-metals?

A

Reaction of non-metals with hydrogen gives an acid

Hydrogen + Non-metal -> Acid

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82
Q

Give equations to show the preparation of acids from non-metals

A

H2 + Cl2 -> 2HCl

H2 + I2 -> 2HI

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83
Q

How are acids prepared from acidic oxides?

A

Acidic oxides dissolve in water to give an acid

Acidic Oxide + Water -> Acid

84
Q

Give equations to show the preparation of acids from acidic oxides

A

CO2 + H2O -> H2CO3 (carbonic)
SO2 + H2O -> H2SO3 (sulphurous)
SO3 + H2O -> H2SO4 (sulphuric)
P2O5 + 3H2O -> 2H3PO4 (phosphoric)

85
Q

Name the acidic oxides used to prepare acids

A

Carbon dioxide, Sulphur dioxide, Sulphur trioxide, Phosphorous pentoxide

86
Q

Which oxides do not produce an acid when made to react with water?

A

Neutral oxides - Carbon monoxide (CO), Nitric oxide (NO)

87
Q

How are acids prepared from salts?

A

Non-volatile acids on heating with salts of more volatile acids, displace the volatile acid
Normal salt + Sulphuric acid (conc.) -> Acid salt + Displaced volatile acid

88
Q

Give equations to show the preparation of acids from salts

A

KNO3 + H2SO4 -> (<200 C) KHSO4 (Potassium bisulfate)+ HNO3

NaCl + H2SO4 -> (<200 C) NaHSO4 (Sodium bisulfate) + HCl

89
Q

Name two volatile acids

A

Hydrochloric, Nitric

90
Q

Name two acid salts

A

Potassium bisulfate, Sodium bisulfate

91
Q

How are acids prepared from oxidation of nonmetals?

A

Non-metal is oxidised by conc. acid to give an acid

Sulphur + Nitric Acid -> Sulphuric acid + water + nitrogen dioxide

92
Q

Give an equation to show the preparation of acids by oxidation of non-metals

A

S + 6HNO3 -> H2SO4 + 2H2O + 6NO2

93
Q

What is the nature of acidic oxides?

A

Non-metallic

94
Q

How are acidic oxides formed?

A

On reaction of non metal with oxygen

95
Q

Name the ways to prepare bases

A
  1. From Metals
  2. From Basic Oxides
  3. From Salts
  4. By Decomposition of salts
  5. By Active Metals
96
Q

How are bases prepared from metals?

A

Reaction of a metal with oxygen gives a base (basic oxide)

Metal + Oxygen -> Basic Oxide

97
Q

Give equations to show the preparation of bases from metals

A

4Na + O2 -> 2Na2O (sodium oxide)

2Mg + O2 -> 2MgO (magnesium oxide)

98
Q

How are bases prepared from basic oxides?

A

Basic oxides (soluble) dissolve in water to give a base (alkali)

99
Q

Give equations to show the preparation of bases from basic oxides

A

K2O + H2O -> 2KOH

Na2O + H2O -> 2NaOH

100
Q

How are bases prepared from active metals?

A

Active metals react with water to give a base (alkali)

101
Q

Give equations to show the preparation of bases from active metals

A

2K + 2H2O -> 2KOH + H2

2Na + 2H2O -> 2NaOH + H2

102
Q

How are bases prepared from salts?

A

Aqueous solutions of salts with a strong base precipitates the base (metallic hydroxide)

Salt soln. + Base (alkali) -> Normal salt + Precipitated basic hydroxide

103
Q

Give equations to show the preparation of bases from salts

A

AlCl3 + 3NaOH -> 3NaCl + Al(OH)3 ↓

FeSO4 + 2NaOH -> Na2SO4 + Fe(OH)2 ↓

104
Q

How are bases prepared by decomposition of salts?

A

Heat on certain carbonates or nitrates gives a base [basic oxide]
Lead nitrate -> Lead oxide + nitrogen dioxide + oxygen

105
Q

Give equations to show the preparation of bases by decomposition of salts

A

Lead nitrate -> Lead oxide + nitrogen dioxide + oxygen

2Pb (NO3)2 -> 2PbO + 4NO2 + O2

106
Q

Name some basic oxides

A

Na2O, 2MgO, K2O, PbO

Sodium, Magnesium, Potassium, Lead Oxides

107
Q

Give the physical properties of acids

A
  1. Sour in taste in aqueous solution
  2. Mineral acids [HCl, HNO3, H2SO4] - highly corrosive
  3. Indicators - Turns blue (purple) litmus red
108
Q

Give the physical properties of bases

A
  1. Bitter in taste in aq. soln.
  2. Caustic alkalis [KOH, NaOH] - highly corrosive
  3. Indicators - Turns red litmus blue
109
Q

Give the chemical properties of acids

A
  1. Acids neutralize bases to give salt and water only
  2. Acids react with active metals to liberate hydrogen
  3. The less volatile acid displaces the more volatile on heating with salt
110
Q

Give examples of neutralization reactions

A
  1. CuO + H2SO4 -> CuSO4 + H2O

2. NaOH + HCl -> NaCl + H2O

111
Q

Give example of reactions of acids (dil.) with active metals

A

Zn + 2HCl -> ZnCl2 + H2

112
Q

How is nitric acid formed on heating a more volatile acid with salt?

A

NaNO3 (salt) + H2SO4 (conc.) -> (<200 C) NaHSO4 (salt) + HNO3

113
Q

When is unstable H2CO3 formed?

A

2NaHCO3 + H2SO4 (dil.) -> Na2SO4 + (2H2O + 2CO2)

Na2CO3 + 2HCl (dil.) -> 2NACl + (H2O + CO2)

114
Q

Give chemical properties of bases

A
  1. Alkalis react with ammonium salts on heating to liberate ammonia
  2. A less volatile base displaces the more volatile base
  3. Alkalis react with certain metallic salt solutions to precipitate insoluble hydroxides
115
Q

Define neutralizatoin

A

The process due to which [H+] ions of an acid react completely or combine with [OH-] ions of a base to give salt and water only

116
Q

What happens during neutralization (detail)?

A

The hydrogen ion [H+] or proton from the acid is neutralized by the hydroxyl ions [OH-] from the alkali to form a water molecule [H2O]. Thus HCl donates a H+ ion to the OH- ion of NaOH which accepts the proton forming water

117
Q

What is heat of neutralization?

A

The amount of heat liberated when 1 gram equivalent of an acid or a base is completely neutralized

118
Q

Which acid is used in eye wash?

A

Boric acid

119
Q

Which acid is used in food preservation?

A

Citric acid

120
Q

Which acid is used in ink stain remover??

A

Oxalic acid

121
Q

Which acid is used in flavoring drinks?

A

Carbonic acid

122
Q

Which acid is used in baking powder?

A

Tartaric acid

123
Q

Which acid is used incooking?

A

Acetic acid (vinegar)

124
Q

Which acid is used in pickling of metals?

125
Q

Which base is used in manufacture of soaps?

A

Sodium hydroxide (NaOH)

126
Q

Which base is used in manufacture of bleaching powder?

A

Calcium hydroxide

127
Q

Which base is used as an antacid?

A

Magnesium hydroxide

128
Q

Which base is used in fire extinguishers?

A

Aluminium hydroxide

129
Q

Which base is used in softening water?

A

Calcium hydroxide

130
Q

Which base is used in removing grease stains from clothes?

A

Ammonium hydroxide

131
Q

What is the function of an antacid?

A

To neutralize acidity

132
Q

Name the two uses of CaOH

A
  1. Manufacture of bleaching powder

2. In softening water

133
Q

What is the pH of anything acidic in nature?

A

less than 5.6

134
Q

What is acid rain?

A

It refers to rain or any precipitation which is acidic in nature

135
Q

What is acid rain a mixture of?

A

It is generally a complex mixture of sulphuric acid [H2SO4] along with sulphurous acid [H2SO3] & nitric acid [HNO3] along with nitrous acid [HNO2]

136
Q

What causes acid rain?

A

Atmospheric pollutants - mainly sulphur dioxide and nitrogen oxides

137
Q

What is the impact of acid rain?

A
  1. It depletes the soil of nutrients
  2. Increases the acidity of the soil
  3. Reduces the fertility of the soil
  4. Destroys marine life due to change in pH of envnt.
  5. Causes material damage
138
Q

When is 2NO formed?

A

At high temperatures, which are achieved during -

  1. lightning discharge in the atmosphere
  2. operation of internal combustion engines
139
Q

How are nitrous and nitric acids formed?

A

NO2 reacts with water vapour forming these acids
H2O + 2NO2 -> HNO2 + HNO3
[2H2O + 4NO2 + O2 -> 4HNO3]

140
Q

What are indicators?

A

Weak organic compounds (acids or bases) which change color in accordance with the pH of the solution

141
Q

What do indicators produce on dissociating slightly in solution?

A

Ions and undissociated molecules

142
Q

What is the color of the ions produced dependent on?

A

Hydrogen ion concentration or pH of the medium

143
Q

Define pH

A

The negative logarithm (to the base 100 of the hydrogen ion concentration expressed in moles/litre

144
Q

What is the pH of pure water?

A

7 ( [H+ aq.] = [OH-] )

145
Q

Give the value of pH

A

pH = -log ↓10 H+

146
Q

What does the pH value represent?

A

The strength of acids and alkalis expressed in terms of hydrogen ion concentration [H+ aq.]

147
Q

What does pure water yield on ionization?

A

Equal no. of hydrogen ions and hydroxyl ions

148
Q

What is the conc. of H+ ions and OH- ions equal to?

A

both equal to 10^-7 mol. dm^-3 [at 25 C]

149
Q

What is the ionic product of water?

A

Kw = [H+] [OH-] = 10^-7 * 10^-7 = 10^-14 [at 25 C]

150
Q

What happens to the H+ and OH- conc. of an aq. medium when an acid is added to it?

A

The H+ ion conc. increases to above 10^-7 and at the same time, the OH- ion conc. decreases to below 10^-7

151
Q

What is the pH of an acidic medium?

A

Less than 7 ([H+ aq.] more than [OH-])

152
Q

What is the pH of a basic medium?

A

More than 7 ( [OH-] more than [H+ aq.] )

153
Q

Name some common acid-base indicators

A
  1. Litmus
  2. Methyl orange
  3. Phenolphthalein
154
Q

What are universal indicators?

A

Universal indicators are mixtures of organic dyes or mixed indicators

155
Q

Name some common universal indicators

A

pH paper or solution

156
Q

What is an acid-base indicator used for?

A

Indicating whether a solution is acidic or alkaline

157
Q

What can an acid-base indicator not be used for?

A

For determining the strength of the acidic or alkaline soln.

158
Q

What can an acid-base indicator not differentiate between?

A

Acidic or basic solutions of different pH values, since they change their colors abruptly at a certain pH value

159
Q

When does methyl-orange change color abruptly?

160
Q

What can a universal indicator indicate?

A

The strength or pH range of the acidic or alkaline soln.

161
Q

What are the utilities of a universal indicator not possessed by an acid-base indicator?

A
  1. It can determine the strength of acidic or alkaline solutions
  2. It can differentiate between acidic or basic solutions of different pH values, by giving different colors with different pH values
162
Q

When does color change from blue to indigo to violet?

A

between pH 7-14

163
Q

How is a litmus indicator obtained?

A

It is a natural coloring matter obtained from certain lichens

164
Q

How is a litmus soln. prepared?

A

By dissolving 0.5 g of litmus in 1 litre of distilled water and filtering

165
Q

What color is litmus when substance is NAA?

A

Purple - Neutral, Red - Acidic, Blue - Alkaline

166
Q

What color is methyl orange when substance is NAA?

A

Orange - Neutral, Pink - Acidic, Yellow - Alkaline

167
Q

What color is phenolphthalein when substance is NAA?

A

Colourless - Neutral, Colorless - Acidic, Pink - Alkaline

168
Q

What color is phenolphthalein (alkaline) when substance is NAA?

A

Pink - Neutral, Colorless - Acidic, Pink - Alkaline

169
Q

What is the color in the PH range from 0-7?

A

Red, orange, yellow, green
Reddish orange for strongly acidic
Yellowish green for weakly acidic

170
Q

What is the color in the PH range for 7?

171
Q

What is the color in the PH range from 7-14?

A

Green, Blue, Indigo, Violet
Greenish Blue when weakly alkaline
Violet when strongly alkaline

172
Q

What is the utility of indicators in agriculture?

A

The pH of the soil is tested for better growth of crops

173
Q

What type of medium do citrus fruits need?

A

Slightly alkaline soil

174
Q

What type of medium does rice need?

A

An acidic medium

175
Q

What type of medium does sugarcane need?

A

A neutral medium

176
Q

What is the utility of indicators in dairies?

A

A change in pH of milk - from pH 6.6 indicates that the milk has turned sour

177
Q

What is the utility of indicators in technology?

A

Bio-chemical and organic reactions are carried out under controlled pH

178
Q

What is the utility of indicators in medicine?

A

pH values of urine and blood are taken for diagnosis of various diseases

179
Q

What is the pH value of human blood?

180
Q

What is the pH value of sea water?

181
Q

What is the pH value of grapes (tartaric acid)?

182
Q

What is the pH value of lactic acid (milk)?

183
Q

What is the pH value of vinegar (acetic acid)?

184
Q

Name some acidic solutions

A
  1. Dil. HCl
  2. Dil. H2SO4
  3. Acetic acid
  4. Tartaric acid
  5. Lactic acid
185
Q

Name some alkaline solutions

A
  1. Human blood
  2. Albumin
  3. Sea water
  4. Ammonium Hydroxide
  5. Sodium hydroxide
186
Q

What is a salt?

A

It is a compound formed by partial or complete replacement of the replaceable (ionizable) hydrogen ion of an acid by a metallic ion or ammonium ion (basic radical)

187
Q

What does salt yield on dissociation?

A

A positive ion (other than a hydrogen ion [H+] & a negative ion other than hydroxyl ion [OH-]

188
Q

What is an acid salt?

A

The salt formed by partial replacement of the replaceable hydrogen ion of an acid molecule by a basic radical (metallic or ammonium ion)

189
Q

How is an acid salt prepared?

A

Formed when the amount of base taken is insufficient for complete neutralization of an acid by a base

190
Q

What does an acid salt exhibit?

A

All properties of an acid in solution - ionizes to give H+/ H3O+ ions

191
Q

What is a normal salt?

A

The salt formed by complete replacement of the replaceable hydrogen ion of an acid molecule by a basic radical (metallic or ammonium ion)

192
Q

How is a normal salt prepared?

A

Formed when the amount of base taken is sufficient or in excess for complete neutralization of an acid by a base

193
Q

What does a normal salt exhibit?

A

Not the properties of an acid in solution

194
Q

How is a basic salt formed?

A

By partial replacement of hydroxyl radicals of a diacidic or triacidic base with an acid radical

195
Q

What does a basic salt contain?

A 
A cation (metallic), a hydroxyl ion (of a base), an anion 
(of an acid)
196
Q

How is a double salt formed?

A

Formed by mixing saturated solutions of two simple salts followed by crystallization of the saturated soln.

197
Q

What does a double salt consist of?

A

A mixture of two simple salts (chemically combined)

198
Q

Give examples of double salts

A
  1. Alum (potash alum)

2. Ferrous ammonium sulphate (Mohr’s salt)

199
Q

What is a mixed salt?

A

Contains 2 or more basic radicals or acid radicals

200
Q

Give examples of a mixed salt

A
  1. Sodium potassium carbonate

2. Bleaching powder

201
Q

How is a complex salt formed?

A

Formed by mixing saturated solutions of simple salts followed by crystallization of the saturated solutions

202
Q

What does a complex salt consist of?

A

A simple ion and a complex ion (formed on dissociation)

203
Q

Give examples of complex salts

A
  1. Potassium mercuric iodide
  2. Sodium silver cyanide
  3. Sodium zincate
  4. Tetrammine copper [II] sulphate
204
Q

What is Nesseler’s Reagent for testing Ammonia gas?

A

Potassium mercuric iodide

205
Q

What is used as an electrolyte in the electroplating of silver?

A

Sodium silver cyanide

Chemistry (4 decks)

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