Medical Chemistry Lecture 1

Introduction to Medical Chemistry

• Chemistry is the study of matter, including its structure, composition, and changes that occur when exposed to various situations.
• Chemistry investigates the qualities of matter and how and why it changes.

Branches of Chemistry

• Chemistry has five main disciplines:
  • Organic chemistry: studies chemicals containing carbon.
  • Inorganic chemistry: studies chemicals that do not contain carbon.
  • Physical chemistry: studies the rates of chemical reactions and physical structure of materials at the molecular level.
  • Analytical chemistry: studies the composition of substances.
  • Biochemistry: studies chemical processes in living things.

Structure of an Atom

• An atom is the smallest particle of an element and cannot be divided into smaller parts by ordinary chemical processes.
• An atom consists of:
  • Protons (positive charge) in the nucleus.
  • Neutrons (no charge) in the nucleus.
  • Electrons (negative charge) surrounding the nucleus.
• Virtually all of an atom's mass is in the protons and neutrons in the nucleus.
• Electrons surrounding the nucleus have almost no mass.

Atomic Number and Mass Number

• Atomic number: indicates the number of protons in an atom.
• Mass number: the number of protons and neutrons in the nucleus.

States of Matter

• Solid state: strong attraction forces between molecules.
• Liquid state: average attraction forces between molecules.
• Gas state: negligible attraction forces between molecules.

Chemical Properties of Matter

• Reactivity: the tendency of matter to combine chemically with other substances.
• Flammability: the tendency of matter to burn.
• Toxicity: the extent to which a chemical element or combination of chemicals may harm an organism.
• Acidity: a substance's ability to react with an acid.