Atomic Structure Quiz

Study Notes

Atomic Structure

Protons, Electrons, and Neutrons:
- Zinc (Zn): Protons - 30, Electrons - 30, Neutrons - 35
- Magnesium (Mg): Protons - 12, Electrons - 12, Neutrons - 12
- Iron (Fe): Protons - 26, Electrons - 26, Neutrons - 30
- Chromium (Cr): Protons - 24, Electrons - 24, Neutrons - 28
- Cobalt (Co): Protons - 27, Electrons - 27, Neutrons - 32
- Titanium (Ti): Protons - 22, Electrons - 22, Neutrons - 26
- Silicon (Si): Protons - 14, Electrons - 14, Neutrons - 14
- Calcium (Ca): Protons - 20, Electrons - 20, Neutrons - 20
- Elements with atomic numbers 21-24:
  - Scandium (Sc): Protons - 21, Electrons - 21, Neutrons - 24
  - Titanium (Ti): Protons - 22, Electrons - 22, Neutrons - 26
  - Vanadium (V): Protons - 23, Electrons - 23, Neutrons - 28
  - Chromium (Cr): Protons - 24, Electrons - 24, Neutrons - 28
Rutherford's Atomic Model:
- Atoms are mostly empty space
- Dense, positively charged nucleus at the center
- Negatively charged electrons orbit the nucleus
Bohr's Theory:
- Electrons exist in specific energy levels or orbits around the nucleus
- Electrons can jump between energy levels by absorbing or emitting energy
Atomic Theory:
- All matter is made up of atoms, which are the smallest units of an element
- Atoms of the same element are identical, but differ from atoms of other elements
- Atoms cannot be created or destroyed, only rearranged
Avogadro's Number: 6.022 x 10^23, represents the number of particles (atoms, molecules, ions) in one mole of a substance
Thomson Model:
- Atoms are a sphere of positive charge with negatively charged electrons embedded within it, like a plum pudding
Isotopes:
- Atoms of the same element with differing numbers of neutrons
Chemical Properties of Matter:
- How a substance interacts with other chemicals
Physical Properties of Matter:
- Characteristics observed without changing the substance's composition

States of Matter

Types of Matter:
- Pure Substances: Fixed composition and properties, Elements or compounds
- Mixtures: Variable composition, Two or more substances physically combined
- Elements: Fundamental substances that cannot be broken down further
- Compounds: Two or more elements chemically bonded
States of Matter:
- Gas: Indefinite shape and volume, easily compressible, particles move randomly
- Liquid: Fixed volume, indefinite shape, particles move more freely than solids
- Solid: Definite shape and volume, particles tightly packed and vibrate
- Liquid Crystal: Ordered arrangement of molecules, resemble liquid in flow but have properties like solids

Chemical/Molecular Formulas

Chemical Formula: Representation of a substance using chemical symbols and subscripts (e.g., H2O for water)
Molecular Formula: Shows the actual number of atoms of each element in a molecule (e.g., H2O for a water molecule)

Gay-Lussac's Law

Statement: At constant volume, the pressure of a gas is directly proportional to its absolute temperature (expressed in Kelvin): P/T = constant
Applications:
- Designing pressure vessels to withstand temperature changes
- Predicting the pressure or temperature of a gas in a sealed container

Radioactivity

Chemical reaction: Involves the rearrangement of atoms and breaking and forming of bonds
Radioactivity: The spontaneous emission of particles or energy from the nucleus of an unstable atom
Examples:
- Nuclear power generation: Radioactive decay is used to produce heat and electricity
- Medical imaging: Radioactive isotopes are used to diagnose and treat diseases

Structure of Atom

Proton:
- Positively charged particle located in the nucleus
- Determines the element
Electron:
- Negatively charged particle orbiting the nucleus
- Involved in chemical bonding
Neutron:
- Neutral particle located in the nucleus
- Contributes to the atom's mass

Periodic Table

Element Position: Elements are arranged in order of increasing atomic number
Atomic Number: Number of protons in an atom
Atomic Mass: Average mass of an atom of an element, taking into account the abundance of its isotopes
Isotopes: Atoms of the same element that have different numbers of neutrons

Molecules and Ions

Molecule: Two or more atoms bonded together
- Examples: H2O (water), CO2 (carbon dioxide)
Ion: An atom or molecule that has gained or lost electrons, giving it a net electric charge
- Examples: Na+ (sodium ion), Cl- (chloride ion)
- Ions form ionic compounds, held together by electrostatic attractions