2. Properties and Reactions of Substance

Properties of Common Inorganic Substances

1. Elements

   • Basic building blocks of matter.

   • Cannot be broken down into simpler substances.

   • Examples: Hydrogen (H), Oxygen (O), Carbon (C).

2. Oxides

   • Compounds formed when elements react with oxygen.

   • Types:

     • Metallic Oxides: Formed by metals (e.g., Na_2O, sodium oxide).

     • Non-metallic Oxides: Formed by non-metals (e.g., CO_2, carbon dioxide).

3. Acids

   • Substances that produce hydrogen ions (H+) in solution.

   • Properties: Sour taste, can turn blue litmus paper red.

   • Examples: Sulfuric acid (H2SO4), Hydrochloric acid (HCl).

4. Bases

   • Substances that produce hydroxide ions (OH-) in solution.

   • Properties: Bitter taste, slippery feel, can turn red litmus paper blue.

   • Examples: Sodium hydroxide (NaOH), Ammonia (NH3).

5. Salts

   • Formed from the neutralization of acids and bases.

   • Composed of cations from bases and anions from acids.

   • Example: Sodium chloride (NaCl).

Basic Organic Compounds

1. Hydrocarbons

   • Compounds composed primarily of hydrogen and carbon.

   • Types:

     • Alkanes: Saturated hydrocarbons (e.g., methane, CH_4).

     • Alkenes: Unsaturated hydrocarbons with double bonds (e.g., ethylene, C2H4).

     • Alkynes: Unsaturated hydrocarbons with triple bonds (e.g., acetylene, C2H2).

2. Hydrocarbon Derivatives

   • Compounds that contain other elements in addition to carbon and hydrogen (e.g., alcohols, halides).

   • Example: Ethanol (C2H5OH), a derivative of ethane.

Identification of Reactions

1. Redox Reactions

   • Reactions involving the transfer of electrons.

   • Oxidation: Loss of electrons.

   • Reduction: Gain of electrons.

   • Example: Zn + Cu^{2+}
     ightarrow Zn^{2+} + Cu.

2. Ionic Reactions

   • Reactions involving the exchange of ions in solution.

   • Can occur in the form of double displacement reactions.

   • Example: NaCl + AgNO3 ightarrow AgCl + NaNO3 (formation of a precipitate).

3. Testing Methods

   • Litmus Test: Used to identify acids and bases.

   • Precipitation Tests: Used to identify ions in solution by observing the formation of a solid (precipitate).

   • Oxidation States: Analyzing changes in oxidation states to identify redox processes.

1. Basic Formulas of Inorganic Substances

   • Acids:

     • General formula: HA, where H represents hydrogen and A represents the anion.

     • Example: Sulfuric acid: H2SO4.

   • Bases:

     • General formula: BOH, where B represents the cation and OH represents the hydroxide ion.

     • Example: Sodium hydroxide: NaOH.

   • Salts:

     • General formula: MX, where M is the cation and X is the anion.

     • Example: Sodium chloride: NaCl.

2. Basic Formulas of Organic Compounds

   • Hydrocarbons:

     • General formulas:

     • Alkanes: CnH{2n+2}, where n is the number of carbon atoms.

       • Example: Methane: CH_4 (where n=1).

     • Alkenes: CnH{2n}.

       • Example: Ethylene: C2H4 (where n=2).

     • Alkynes: CnH{2n-2}.

       • Example: Acetylene: C2H2 (where n=2).

   • Hydrocarbon Derivatives:

     • Example: Ethanol: C2H5OH, derived from ethane.

3. Reactions

   • Redox Reactions:

     • General representation: A + B
       ightarrow A^+ + B^-.

     • Example: Zn + Cu^{2+}
       ightarrow Zn^{2+} + Cu.

   • Ionic Reactions:

     • General representation: AX + BY
       ightarrow AY + BX.

     • Example: NaCl + AgNO3 ightarrow AgCl + NaNO3.

   • Testing Methods:

     • Litmus Test:

     • In acidic solutions, blue litmus turns red.

     • In basic solutions, red litmus turns blue.

     • Precipitation Tests:

     • Example: Adding BaCl2 to Na2SO4 results in a white precipitate of barium sulfate, BaSO4.

     • Oxidation States:

     • Example: Zn in Zn^{2+} is oxidized, while Cu^{2+} is reduced in the redox reaction.