Organic Chemistry AHS 111: Atomic Structure Quiz

Course Information

• Course Title: Organic Chemistry (AHS 111)
• Level: 1st level
• Semester: 1st semester
• Subject Instructor: Dr./ Hجاج حسن
• Institution: SPHINX University
• Department: Faculty of Applied Health Sciences Technology
• Intended Audience: Pharm D Students

Atomic Structure and Theory

• Dalton's Atomic Theory:
  • Elements composed of extremely small particles called atoms.
  • All atoms of a given element are identical.
  • Atoms of different elements are different.
  • Atoms of one element cannot be changed into different elements.
  • Compounds formed when atoms of more than one element combine.
• Rutherford's Model:
  • Atom contains a very small, dense nucleus.
  • Electrons are around the outside of the atom.
  • Most volume of the atom is empty space.

Subatomic Particles

• Protons: Discovered by Rutherford in 1919.
• Neutrons: Discovered by James Chadwick in 1932.
• Electrons: Negatively charged.
• Mass of Electron Compared to Proton & Neutron: Negligibly small compared to the mass of protons and neutrons.
• Charge of Subatomic Particles: Protons (positive), Neutrons (neutral), and Electrons (negative).

Symbols of Elements

• Elements represented by one or two letters.
• Atomic number (Z): The number of protons in an atom of an element.
• Mass number: The sum of the number of protons and neutrons in an atom.

Isotopes

• Atoms of the same element that have different numbers of neutrons.
• Example: Different isotopes of carbon (¹¹C, ¹²C, ¹³C, ¹⁴C).

The Periodic Table

• Rows are called periods.
• Columns are called groups.
• Elements in the same group have similar chemical properties.
• Metallic elements are on the left side.
• Nonmetals are on the right side.

Atomic Mass

• Average mass calculated from isotopes weighted by their relative abundances.
• Atomic weight = ∑[(isotope mass) × (fractional isotope abundance)] over all isotopes of the element

Diatomic Molecules

• Seven elements occur naturally as molecules containing two atoms (H₂, N₂, O₂, F₂, Cl₂, Br₂, I₂).

Chemical Formulas

• Subscripts indicate the number of atoms of each element in a molecule.
• Molecular compounds usually contain only nonmetals.
• Examples include H₂O (water), CO₂ (carbon dioxide).

Types of Formulas

• Empirical formula: Lowest whole-number ratio of atoms.
• Molecular formula: Exact number of atoms.
• Structural formula: Shows bonding order.
• Perspective drawings: Show three-dimensional arrangement.

Ions

• Atoms gain or lose electrons to form ions.
• Cations (positive): Formed by elements on the left of the periodic table.
• Anions (negative): Formed by elements on the right of the periodic table.

Ionic Bonds

• Ionic compounds (like NaCl) formed between metals and nonmetals.
• Metals lose electrons to form positively charged ions (cations).
• Nonmetals gain electrons to form negatively charged ions (anions).

Practice Questions

• Practice Problems: Provided in various slides to test understanding of the concepts learned. Problems for determining number of subatomic particles, writing chemical symbols, identification of ionic and molecular compounds.