7.3.2
Preparing Soluble Salts
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Preparing Soluble Salts
Soluble salts are prepared by reacting acids with alkalis, metals, bases, or carbonates. Steps involve reaction, filtration, evaporation for crystals, and drying.

Introduction to soluble salts preparation
- Soluble salts dissolve well in water.
- Chemists prepare soluble salts by reacting acids with other substances.
- The four main methods: titration with alkali, excess metal, excess insoluble base, and excess insoluble carbonate.
- Each method requires separation and purification steps.

Preparation by titration with alkali
- Use an acid and an alkali to make soluble salts by titration.
- Slowly add alkali to acid until neutralisation occurs (pH 7).
- Record the exact volumes when neutral.
- Repeat without indicator, then evaporate water to crystallise salt.
- Separate crystals by filtration and dry them.

Preparation using excess metal, base or carbonate
- React acid with excess metal (like zinc), base (like copper oxide), or carbonate (like calcium carbonate).
- The acid reacts until all the acid is used up.
- Filter to remove leftover solids.
- Evaporate the filtrate to crystallise pure soluble salt.

Separation and purification of salts
- After reaction, solutions must be filtered to remove solids.
- Evaporate the solution gently to form crystals.
- Crystals form as the solution concentrates.
- Dry crystals with filter paper to purify.
- This process yields pure soluble salts for experiments.

Hydrated and anhydrous substances
- Hydrated substances contain water molecules chemically joined.
- Anhydrous substances have no water.
- Example: Copper sulfate turns blue when hydrated, white when anhydrous.
- Water of crystallisation affects the appearance and properties.
1States of Matter
1.1Solids, Liquids, & Gases
2Atoms, Elements & Compounds
2.1Elements, Compounds & Mixtures
2.2Atomic Structure & the Periodic Table
2.3Isotopes
2.4Ions & Ionic Bonds
2.5Simple Molecules & Covalent Bonds
2.6Giant Covalent Structures
2.7Metallic Bonding
3Stoichometry
3.1Formulae
3.2Relative Masses of Atoms & Molecules
3.3The Mole & the Avogadro Constant
3.3.1Introducing Moles3.3.2Amounts of Substances3.3.3Moles & Equations3.3.4Calculations Involving Gases3.3.5Calculating Stoichiometric Reacting Masses3.3.6Calculating the Moles of Solute3.3.7Calculating Empirical Formula3.3.8Chemical Equations3.3.9Percentage Yield3.3.10Calculating Yield3.3.11Percentage Purity
4Electrochemistry
4.1Electrolysis
4.1.1Electrolytic Process4.1.2Electrolysis Examples4.1.3Electrolysis of a Binary Compound in Molten State4.1.4Electroplating4.1.5Transfer of Charge During Electrolysis4.1.6Electrolysis of Aqueous Solutions4.1.7Electrolysis of Copper Sulfate4.1.8Electrolysis of Halide Compounds4.1.9Half-Equations4.1.10Combustion of Hydrocarbons
4.2Hydrogen–Oxygen Fuel Cells
5Chemical Energetics
6Chemical Reactions
6.1Physical & Chemical Changes
6.2Rate of Reaction
6.3Reversible Reactions & Equilibrium
6.3.1Reversible Reactions6.3.2Conditions & Equilibrium6.3.3Dynamic Equilibrium6.3.4Changing Conditions - Heat & Water Effects6.3.5Factors Affecting Equilibria - Temperature6.3.6Factors Affecting Equilibria - Pressure6.3.7Factors Affecting Equilibria - Concentration6.3.8The Haber Process6.3.9The Haber Process Equation
7Acids, Bases & Salts
7.1The Characteristic Properties of Acids & Bases
7.1.1Acids & Alkali7.1.2Reactions of Metals with Acids7.1.3Reactions of Bases with Acids7.1.4Reactions of Carbonates with Acids7.1.5Identifying Acids7.1.6Properties & Effects of Acids7.1.7Properties of Bases - Reactions with Acids & Salts7.1.8Properties of Alkalis & Indicators7.1.9Strong vs Weak Acids7.1.10Strong vs Weak Bases7.1.11Understanding Universal Indicator Paper7.1.12Acids, Bases & the Neutralisation Reaction
8The Periodic Table
8.1Arrangement of Elements
8.2Group I Properties
8.3Group VII Properties
8.4Transition Elements
8.5Noble Gases
9Metals
9.1Properties of Metals
9.2Uses of Metals
9.3Alloys & Their Properties
9.4Reactivity Series
9.5Corrosion of Metals
9.6Extraction of Metals
10Chemistry of the Environment
10.1Water
10.2Fertilisers
11Organic Chemistry
11.1Formulae, Functional Groups & Terminology
11.2Naming Organic Compounds
11.3Fuels
11.4Alkanes
11.5Alkenes
11.6Alcohols
11.7Carboxylic Acids
11.8Polymers
11.8.1Polymers11.8.2Problems With Polymers11.8.3Polymers & Plastics11.8.4Problems with Plastics11.8.5Condensation Polymerisation11.8.6Condensation Polymerisation Examples11.8.7Addition Polymerisation11.8.8Addition Polymerisation Examples11.8.9Structure of Polymers11.8.10Natural Polyamides - Proteins & Amino Acids
12Experimental Techniques & Chemical Analysis
12.1Experimental Design
12.2Acid-base Titrations
12.3Chromatography
12.4Separation & Purification
12.5Identification of Ions & Gases
12.5.1Testing Aqueous Cations 112.5.2Testing Aqueous Cations 212.5.3Testing Cations - Flame Tests12.5.4Testing Cations12.5.5Testing for Aqueous Cations12.5.6Testing Anions - Sulfates12.5.7Testing Anions - Nitrates12.5.8Testing Gases - Hydrogen12.5.9Testing Gases - Oxygen12.5.10Testing Gases - Carbon Dioxide12.5.11Testing Gases - Chlorine12.5.12Identifying Gases
Jump to other topics
1States of Matter
1.1Solids, Liquids, & Gases
2Atoms, Elements & Compounds
2.1Elements, Compounds & Mixtures
2.2Atomic Structure & the Periodic Table
2.3Isotopes
2.4Ions & Ionic Bonds
2.5Simple Molecules & Covalent Bonds
2.6Giant Covalent Structures
2.7Metallic Bonding
3Stoichometry
3.1Formulae
3.2Relative Masses of Atoms & Molecules
3.3The Mole & the Avogadro Constant
3.3.1Introducing Moles3.3.2Amounts of Substances3.3.3Moles & Equations3.3.4Calculations Involving Gases3.3.5Calculating Stoichiometric Reacting Masses3.3.6Calculating the Moles of Solute3.3.7Calculating Empirical Formula3.3.8Chemical Equations3.3.9Percentage Yield3.3.10Calculating Yield3.3.11Percentage Purity
4Electrochemistry
4.1Electrolysis
4.1.1Electrolytic Process4.1.2Electrolysis Examples4.1.3Electrolysis of a Binary Compound in Molten State4.1.4Electroplating4.1.5Transfer of Charge During Electrolysis4.1.6Electrolysis of Aqueous Solutions4.1.7Electrolysis of Copper Sulfate4.1.8Electrolysis of Halide Compounds4.1.9Half-Equations4.1.10Combustion of Hydrocarbons
4.2Hydrogen–Oxygen Fuel Cells
5Chemical Energetics
6Chemical Reactions
6.1Physical & Chemical Changes
6.2Rate of Reaction
6.3Reversible Reactions & Equilibrium
6.3.1Reversible Reactions6.3.2Conditions & Equilibrium6.3.3Dynamic Equilibrium6.3.4Changing Conditions - Heat & Water Effects6.3.5Factors Affecting Equilibria - Temperature6.3.6Factors Affecting Equilibria - Pressure6.3.7Factors Affecting Equilibria - Concentration6.3.8The Haber Process6.3.9The Haber Process Equation
7Acids, Bases & Salts
7.1The Characteristic Properties of Acids & Bases
7.1.1Acids & Alkali7.1.2Reactions of Metals with Acids7.1.3Reactions of Bases with Acids7.1.4Reactions of Carbonates with Acids7.1.5Identifying Acids7.1.6Properties & Effects of Acids7.1.7Properties of Bases - Reactions with Acids & Salts7.1.8Properties of Alkalis & Indicators7.1.9Strong vs Weak Acids7.1.10Strong vs Weak Bases7.1.11Understanding Universal Indicator Paper7.1.12Acids, Bases & the Neutralisation Reaction
8The Periodic Table
8.1Arrangement of Elements
8.2Group I Properties
8.3Group VII Properties
8.4Transition Elements
8.5Noble Gases
9Metals
9.1Properties of Metals
9.2Uses of Metals
9.3Alloys & Their Properties
9.4Reactivity Series
9.5Corrosion of Metals
9.6Extraction of Metals
10Chemistry of the Environment
10.1Water
10.2Fertilisers
11Organic Chemistry
11.1Formulae, Functional Groups & Terminology
11.2Naming Organic Compounds
11.3Fuels
11.4Alkanes
11.5Alkenes
11.6Alcohols
11.7Carboxylic Acids
11.8Polymers
11.8.1Polymers11.8.2Problems With Polymers11.8.3Polymers & Plastics11.8.4Problems with Plastics11.8.5Condensation Polymerisation11.8.6Condensation Polymerisation Examples11.8.7Addition Polymerisation11.8.8Addition Polymerisation Examples11.8.9Structure of Polymers11.8.10Natural Polyamides - Proteins & Amino Acids
12Experimental Techniques & Chemical Analysis
12.1Experimental Design
12.2Acid-base Titrations
12.3Chromatography
12.4Separation & Purification
12.5Identification of Ions & Gases
12.5.1Testing Aqueous Cations 112.5.2Testing Aqueous Cations 212.5.3Testing Cations - Flame Tests12.5.4Testing Cations12.5.5Testing for Aqueous Cations12.5.6Testing Anions - Sulfates12.5.7Testing Anions - Nitrates12.5.8Testing Gases - Hydrogen12.5.9Testing Gases - Oxygen12.5.10Testing Gases - Carbon Dioxide12.5.11Testing Gases - Chlorine12.5.12Identifying Gases
Practice questions on Preparing Soluble Salts
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