Solubility Rules, Acids, and Bases

Solubility Rules for Ionic Compounds in Water

• Sodium, potassium, and ammonium compounds are always soluble.
• All nitrates are soluble.
• Chlorides are mostly soluble, with the exception of silver chloride and lead(II) chloride.
• Sulfates are mostly soluble, with the exception of barium sulfate, calcium sulfate, and lead(II) sulfate.
• Carbonates are mostly insoluble, except for sodium, potassium, and ammonium carbonates.
• Hydroxides are mostly insoluble, except for sodium, potassium, and calcium hydroxides (calcium hydroxide is slightly soluble).

Acids and Bases

• Acids are proton (H⁺) donors.
• Bases are proton (H⁺) acceptors.

Acid Reactions

• Hydrochloric acid (HCl) reacts with:
  • Metals to form metal chloride and hydrogen gas.
  • Bases to form salt and water.
  • Carbonates to form salt, water, and carbon dioxide.
• Sulfuric acid (H₂SO₄) reacts with:
  • Metals to form metal sulfate and hydrogen gas.
  • Bases to form salt and water.
  • Carbonates to form salt, water, and carbon dioxide.
• Nitric acid (HNO₃) reacts with:
  • Bases to form salt and water.
  • Carbonates to form salt, water, and carbon dioxide.
  • Nitric acid does not react with metals to produce hydrogen gas.

Bases and Alkalis

• Bases include metal oxides, metal hydroxides, and ammonia.
• Alkalis are bases that are soluble in water, such as NaOH and KOH.

Preparing Soluble Salts

• Soluble salts can be prepared by reacting an acid with an insoluble base (e.g., metal oxide).
• Remove excess insoluble reactant using filtration, then heat the filtrate to evaporate water and obtain crystals.
• Alternatively, they can be prepared by mixing an acid and alkali (neutralization) and evaporating water to obtain crystals.

Preparing Insoluble Salts

• Insoluble salts are prepared by mixing two soluble solutions to form an insoluble precipitate.
• Filter, wash, and dry the precipitate.

Preparing Copper(II) Sulfate Crystals

• Hydrated copper(II) sulfate crystals can be prepared by reacting copper(II) oxide with sulfuric acid.
• Filter and evaporate the solution to form blue crystals of CuSO₄·5H₂O.

Preparing Lead(II) Sulfate

• Lead(II) sulfate is prepared by mixing lead(II) nitrate and sodium sulfate solutions.
• Filter, wash, and dry the white precipitate of PbSO₄.

Acid-Base Indicators

• Litmus is red in acid and blue in alkali.
• Phenolphthalein is colorless in acid and pink in alkali.
• Methyl orange is red in acid and yellow in alkali.

pH Scale

• A pH of 0-3 indicates a strongly acidic solution.
• A pH of 4-6 indicates a weakly acidic solution.
• A pH of 7 is neutral.
• A pH of 8-10 indicates a weakly alkaline solution.
• A pH of 11-14 indicates a strongly alkaline solution.

Universal Indicator

• Universal indicator measures approximate pH by color change across the pH range.

Aqueous Solutions

• Acids are a source of hydrogen ions (H⁺).
• Alkalis are a source of hydroxide ions (OH⁻).

Neutralization

• Alkalis neutralize acids to form salt and water.

Acid-Alkali Titration

• Add acid to alkali (or vice versa) using a burette.
• Use an indicator to determine the endpoint (neutralization).
• Calculate concentration using titration data.

Tests for Gases

• Hydrogen (H₂) burns with a squeaky pop.
• Oxygen (O₂) relights a glowing splint.
• Carbon dioxide (CO₂) turns limewater cloudy.

Calculations

• Amount (mol) = Concentration (mol/dm³) × Volume (dm³)
• This formula can be rearranged to find concentration or volume as needed.

Overview of solubility rules for ionic compounds in water, including rules for sodium, potassium, ammonium, nitrates, chlorides, and sulfates. Also covers properties and reactions of acids and bases, proton donors and acceptors and reactions. Focus on reactions with hydrochloric and sulfuric acids reactions.