unit 1 chem

• Electronic Structure of Atoms

  • Definition: Describes how electrons are arranged in an atom.
  • Key Principles:
  • Electrons occupy energy levels (shells) around the nucleus.
  • Sublevels within shells: s,p,d,fs, p, d, fs,p,d,f.
  • Maximum electrons per sublevel:
  • s=2s = 2s=2, p=6p = 6p=6, d=10d = 10d=10, f=14f = 14f=14.
  • Aufbau principle: Electrons fill the lowest energy levels first.
  • Example: Sodium (NaNaNa): 1s22s22p63s11s^2 2s^2 2p^6 3s^11s22s22p63s1.
• What is the first type of bonding discussed in the material?

  Ionic bonding
• What occurs during ionic bonding?

  Transfer of electrons between a metal and a non-metal, forming positive and negative ions
• What is an example of ionic bonding?

  Sodium chloride (NaCl)
• What are the properties of ionic compounds?

  High melting/boiling points, conduct electricity when molten or dissolved, soluble in water
• What is the second type of bonding discussed in the material?

  Covalent bonding
• How is covalent bonding defined?

  Sharing of electrons between non-metal atoms
• Intermolecular Forces

  1. London Dispersion Forces:

  • Weakest intermolecular force.
  • Arises due to temporary dipoles caused by electron movement.
  • Present in all molecules, especially nonpolar ones.

  1. Dipole-Dipole Forces:

  • Occurs between polar molecules.
  • Example: Hydrogen chloride (HClHClHCl).

  1. Hydrogen Bonding:

  • Strongest type of intermolecular force.
  • Occurs when hydrogen is bonded to highly electronegative atoms (N, O, F).
  • Example: Water (H2OH_2OH2​O).
• What is an example of covalent bonding?

  Water (H2O)
• What are the properties of covalent compounds?

  Low melting/boiling points, do not conduct electricity, insoluble in water (mostly)
• What are multiple bonds in chemistry?

  Atoms share more than one pair of electrons
• What is an example of a double bond?

  Oxygen (O2)
• What is an example of a triple bond?

  Nitrogen (N2)
• In which types of molecules are covalent bonds commonly found?

  Hydrocarbons and other organic compounds
• What is an example of a molecule with single covalent bonds?

  Methane (CH4)
• What is the third type of bonding discussed in the material?

  Metallic bonding
• How is metallic bonding defined?

  Positive metal ions in a sea of delocalized electrons
• What are the properties of metallic compounds?

  Good conductivity (electricity/heat), malleable, ductile, high melting/boiling points
• What does the Law of Conservation of Mass state?

  Mass of reactants = mass of products.
• What are the steps to balance a chemical equation?

  1. Write the unbalanced equation.
  2. Adjust coefficients to balance atoms on both sides.
• What is the balanced equation for the reaction of hydrogen and oxygen to form water?

  2H2 + O2 → 2H2O
• What is a mole in chemistry?

  Amount of substance containing $6.022 \times 10^{23}$ particles.
• What is molar mass?

  Mass of one mole of a substance (in grams).
• What is the molar mass of water (H2O)?

  18 g/mol
• How is molarity calculated?

  Molarity = moles of solute / volume of solution (L).
• What is an empirical formula?

  It is the simplest ratio of atoms in a compound.
• What is the empirical formula for glucose (C6H12O6)?

  CH2O
• What is a molecular formula?

  It represents the actual number of atoms in a compound.
• What is the molecular formula for glucose?

  C6H12O6
• How can you calculate the quantities of reactants and products in a chemical reaction?

  Use a balanced chemical equation.
• In the reaction 2H2 + O2 → 2H2O, how many moles of H2 react with 1 mole of O2?

  2 moles of H2
• What is the topic of the first section in the study material?

  Electronic Structure
• What are the sublevels of electron arrangement?

  • s
  • p
  • d
  • f
• What is the main focus of the section titled "Ionic Bonding"?

  Transfer of electrons
• What is a characteristic of ionic bonding?

  It forms ions and has high melting points
• What is the main focus of the section titled "Covalent Bonding"?

  Sharing of electrons
• What is a characteristic of covalent bonding?

  It forms molecules and has low melting points
• What is the main focus of the section titled "Metallic Bonding"?

  Sea of delocalized electrons
• What is a characteristic of metallic bonding?

  It is a good conductor
• What are the types of intermolecular forces in order of strength?

  1. London forces
  2. Dipole-dipole
  3. Hydrogen bonding