Fundamental Concepts of Chemistry

Fundamental Concepts of Chemistry

• Matter

  • Defined as anything that has mass and occupies space.
  • Exists in three states: solid, liquid, gas.

• Atoms and Molecules

  • Atoms: Basic unit of matter, consisting of protons, neutrons, and electrons.
  • Molecules: Two or more atoms bonded together.

Chemical Bonding

• Ionic Bonds

  • Formed when electrons are transferred from one atom to another.
  • Typically occur between metals and non-metals.

• Covalent Bonds

  • Formed when two atoms share electrons.
  • Usually occur between non-metals.

• Metallic Bonds

  • Involves a sea of shared electrons among a lattice of metal atoms.

Chemical Reactions

• Types of Reactions

  • Synthesis: A + B → AB
  • Decomposition: AB → A + B
  • Single Replacement: A + BC → AC + B
  • Double Replacement: AB + CD → AD + CB
  • Combustion: Hydrocarbon + O₂ → CO₂ + H₂O

• Law of Conservation of Mass

  • Mass is neither created nor destroyed in a chemical reaction.

Acids and Bases

• Acids

  • Substances that release hydrogen ions (H⁺) in solution.
  • Characteristics: sour taste, turn litmus paper red.

• Bases

  • Substances that release hydroxide ions (OH⁻) in solution.
  • Characteristics: bitter taste, slippery feel, turn litmus paper blue.

The Periodic Table

• Organized by increasing atomic number.
• Groups (columns) indicate elements with similar properties.
• Periods (rows) show the number of electron shells.

Stoichiometry

• Involves calculations based on the relationships between reactants and products in a chemical reaction.
• Mole ratio, derived from the balanced chemical equation, is fundamental for calculations.

States of Matter

• Solid

  • Definite shape and volume; particles are closely packed.

• Liquid

  • Definite volume but takes the shape of its container; particles are less organized.

• Gas

  • No definite shape or volume; particles are far apart and move freely.

Thermodynamics in Chemistry

• Endothermic Reactions: Absorb heat.
• Exothermic Reactions: Release heat.
• Enthalpy: Heat content of a system.

Chemical Kinetics

• Study of the rates of chemical reactions.
• Factors affecting reaction rate:
  • Concentration
  • Temperature
  • Surface area
  • Catalysts

Equilibrium

• Dynamic state where the rate of the forward reaction equals the rate of the reverse reaction.
• Le Chatelier's Principle: If a system at equilibrium is disturbed, the system will shift to counteract the disturbance.

Solutions and Solubility

• Solution: Homogeneous mixture of solute and solvent.
• Solubility: Amount of solute that can dissolve in a given amount of solvent at a specific temperature.

Organic Chemistry

• Study of carbon-containing compounds.
• Key functional groups:
  • Hydroxyl (-OH), Carboxyl (-COOH), Amino (-NH₂), Alkyl (-R).

Biochemistry

• Intersection of biology and chemistry focusing on molecules essential for life.
• Major biomolecules:
  • Carbohydrates, Lipids, Proteins, Nucleic acids.

Matter

• Anything that has mass and takes up space
• Exists in three states: solid, liquid, and gas
• Composed of atoms and molecules
  • Atoms are the smallest unit of an element
  • Molecules are formed when two or more atoms bond together

Chemical Bonding

• Ionic Bonding involves the transfer of electrons between atoms
  • Typically occurs between metals and non-metals
• Covalent Bonding involves the sharing of electrons between atoms
  • Usually occurs between non-metals
• Metallic Bonding involves a 'sea' of delocalised electrons shared among metal atoms

Chemical Reactions

• Types of Reactions

  • Synthesis combines reactants to form a single product (A + B → AB)
  • Decomposition breaks down a reactant into multiple products (AB → A + B)
  • Single Replacement one element replaces another in a compound (A + BC → AC + B)
  • Double Replacement involves the exchange of ions between two reactants (AB + CD → AD + CB)
  • Combustion involves the rapid reaction between a substance and oxygen, often producing heat and light (hydrocarbon + O₂ → CO₂ + H₂O)

• Law of Conservation of Mass states that mass is neither created nor destroyed in a chemical reaction

Acids and Bases

• Acids release hydrogen ions (H⁺) in solution
  • Tend to have a sour taste and turn litmus paper red
• Bases release hydroxide ions (OH⁻) in solution
  • Tend to have a bitter taste, feel slippery, and turn litmus paper blue

The Periodic Table

• Organized by increasing atomic number
• Groups (columns) contain elements with similar chemical properties
• Periods (rows) indicate the number of electron shells in an atom

Stoichiometry

• Involves calculations based on the relationships between reactants and products in a chemical reaction
• The mole ratio, derived from the balanced chemical equation, is crucial for stoichiometric calculations

States of Matter

• Solid has a definite shape and volume; particles are closely packed
• Liquid has a definite volume but takes the shape of its container; particles are less organized
• Gas has no definite shape or volume; particles are far apart and move freely

Thermodynamics in Chemistry

• Endothermic Reactions absorb heat from the surroundings
• Exothermic Reactions release heat into the surroundings
• Enthalpy measures the heat content of a system

Chemical Kinetics

• Studies the rates of chemical reactions
• Factors affecting reaction rate include:
  • Concentration of reactants
  • Temperature
  • Surface area of reactants
  • Presence of catalysts

Equilibrium

• A dynamic state where the rate of the forward reaction equals the rate of the reverse reaction
• Le Chatelier's Principle states that a system at equilibrium will shift in a direction to relieve stress

Solutions and Solubility

• Solution a homogeneous mixture of a solute and solvent
• Solubility the maximum amount of solute that can dissolve in a given amount of solvent at a specific temperature

Organic Chemistry

• The study of carbon-containing compounds
• Key functional groups:
  • Hydroxyl (-OH): found in alcohols and sugars
  • Carboxyl (-COOH): found in acids like acetic acid
  • Amino (-NH₂): found in amino acids and amines
  • Alkyl (-R): a general term for any carbon-containing group

Biochemistry

• The study of the chemistry of life
• Major biomolecules:
  • Carbohydrates provide energy and structural support
  • Lipids store energy, act as hormones, and form cell membranes
  • Proteins serve as enzymes, structural components, and transport molecules
  • Nucleic acids (DNA and RNA) carry genetic information

Explore the basics of chemistry, focusing on matter, atoms, and molecules. Delve into different types of chemical bonds and reactions, including ionic, covalent, and metallic bonds. Understand the law of conservation of mass and the various types of chemical reactions.