Overview of Chemistry

Overview of Chemistry

• Definition: The science that studies the composition, structure, properties, and changes of matter.
• Branches:
  • Organic Chemistry: Study of carbon-containing compounds.
  • Inorganic Chemistry: Study of inorganic compounds, typically not containing carbon.
  • Physical Chemistry: Study of how matter behaves on a molecular and atomic level.
  • Analytical Chemistry: Techniques and methods used to determine material composition.
  • Biochemistry: Study of chemical processes within and relating to living organisms.

Fundamental Concepts

• Atoms: Basic units of matter, made up of protons, neutrons, and electrons.
• Molecules: Chemical structures formed when two or more atoms bond together.
• Elements: Pure substances that consist entirely of one type of atom (e.g., Hydrogen, Oxygen).
• Compounds: Substances formed when two or more different elements bond together (e.g., H₂O, CO₂).

The Periodic Table

• Organization: Elements arranged by increasing atomic number.
• Groups/Families: Vertical columns that share similar chemical properties.
• Periods: Horizontal rows corresponding to the number of electron shells.

Chemical Bonds

• Ionic Bonds: Formed through the transfer of electrons from one atom to another.
• Covalent Bonds: Formed by the sharing of electrons between atoms.
• Metallic Bonds: Attraction between positively charged metal ions and the electrons around them.

Chemical Reactions

• Types:
  • Synthesis: Two or more reactants form one product.
  • Decomposition: One reactant breaks down into two or more products.
  • Single Replacement: An element replaces another element in a compound.
  • Double Replacement: Exchange of ions between two compounds.
  • Combustion: A substance combines with oxygen, releasing energy.

Stoichiometry

• Definition: Calculation of reactants and products in chemical reactions.
• Mole Concept: A mole represents (6.022 \times 10^{23}) particles of a substance.
• Balancing Equations: Ensuring the same number of each type of atom on both sides of a chemical equation.

States of Matter

• Solid: Defined shape and volume, particles closely packed.
• Liquid: Defined volume but takes the shape of its container, particles less tightly packed.
• Gas: Neither defined shape nor volume, particles are far apart and move freely.
• Plasma: Ionized gas with free electrons, conducts electricity.

Acids and Bases

• Acids: Substances that donate protons (H⁺), characterized by a sour taste and pH < 7.
• Bases: Substances that accept protons or donate hydroxide ions (OH⁻), characterized by a bitter taste and pH > 7.
• pH Scale: Measures acidity or alkalinity; ranges from 0 (strongly acidic) to 14 (strongly basic), with 7 being neutral.

Thermodynamics in Chemistry

• First Law of Thermodynamics: Energy cannot be created or destroyed, only converted.
• Second Law of Thermodynamics: Total entropy of an isolated system can never decrease over time.

Important Concepts

• Catalysts: Substances that speed up chemical reactions without being consumed.
• Equilibrium: The state where the rate of forward reaction equals the rate of reverse reaction.
• Enthalpy: A measure of the total energy of a system, including internal energy and energy associated with pressure and volume.

Laboratory Techniques

• Titration: Technique to determine concentration of an unknown solution.
• Chromatography: Separation of mixtures based on differential affinities.

Safety in Chemistry

• Personal Protective Equipment (PPE): Safety goggles, gloves, lab coats.
• Proper Waste Disposal: Follow protocols for hazardous and non-hazardous materials.

Overview of Chemistry

• Chemistry explores the composition, structure, properties, and changes of matter.
• Investigates how matter interacts on a molecular and atomic level.

Branches of Chemistry

• Organic Chemistry: Focuses on compounds containing carbon.
• Inorganic Chemistry: Studies compounds typically without carbon.
• Physical Chemistry: Explores the behavior of matter at a molecular and atomic level.
• Analytical Chemistry: Develops techniques and methods to determine the composition of materials.
• Biochemistry: Studies chemical processes within and related to living organisms.

Fundamental Concepts

• Atoms: The smallest unit of matter, composed of protons, neutrons, and electrons.
• Molecules: Formed when two or more atoms bond together.
• Elements: Pure substances consisting solely of one type of atom (e.g., Hydrogen, Oxygen).
• Compounds: Substances formed when two or more different elements bond together (e.g., H₂O, CO₂).

The Periodic Table

• Elements are arranged by increasing atomic number.
• Groups/Families: Vertical columns with elements sharing similar chemical properties.
• Periods: Horizontal rows representing the number of electron shells.

Chemical Bonds

• Ionic Bonds: Formed by the transfer of electrons between atoms, resulting in oppositely charged ions.
• Covalent Bonds: Formed by the sharing of electrons between atoms.
• Metallic Bonds: Attract positively charged metal ions and the surrounding electrons.

Chemical Reactions

• Types:
  • Synthesis: Two or more reactants combine to form one product.
  • Decomposition: One reactant breaks down into two or more products.
  • Single Replacement: An element replaces another element in a compound.
  • Double Replacement: Exchange of ions between two compounds.
  • Combustion: A substance combines with oxygen, releasing energy.

Stoichiometry

• Definition: Calculation of reactants and products in chemical reactions.
• Mole Concept: A mole represents (6.022 \times 10^{23}) particles of a substance.
• Balancing Equations: Ensures the same number of each type of atom on both sides of a chemical equation.

States of Matter

• Solid: Defined shape and volume, particles closely packed.
• Liquid: Defined volume but adopts the shape of its container, particles less tightly packed.
• Gas: No defined shape or volume, particles are far apart and move freely.
• Plasma: Ionized gas with free electrons, conducts electricity.

Acids and Bases

• Acids: Substances that donate protons (H⁺), characterized by a sour taste and pH < 7.
• Bases: Substances that accept protons or donate hydroxide ions (OH⁻), characterized by a bitter taste and pH > 7.
• pH Scale: Measures acidity or alkalinity; ranges from 0 (strongly acidic) to 14 (strongly basic), with 7 being neutral.

Thermodynamics in Chemistry

• First Law of Thermodynamics: Energy cannot be created or destroyed, only converted.
• Second Law of Thermodynamics: The total entropy of an isolated system can never decrease over time.

Important Concepts

• Catalysts: Substances that speed up chemical reactions without being consumed.
• Equilibrium: The state where the rate of forward reaction equals the rate of reverse reaction.
• Enthalpy: A measure of the total energy of a system, including internal energy and stored in pressure and volume.

Laboratory Techniques

• Titration: Technique to determine the concentration of an unknown solution.
• Chromatography: Separation of mixtures based on differential affinities.

Safety in Chemistry

• Personal Protective Equipment (PPE): Safety goggles, gloves, lab coats.
• Proper Waste Disposal: Follow protocols for hazardous and non-hazardous materials.