paper 1

• Which elements are highly reactive and easily form positive ions?

  K, Na, Li, Ca, Mg, C, Zn, Fe, H, Cu
• What do some metals produce when they react with acids?

  Salt and hydrogen gas
• Which metals can be shown reacting with water?

  Potassium, sodium, lithium, calcium, zinc, iron, copper
• What is oxidation in terms of oxygen gain?

  Oxidation is the gain of oxygen
• What is reduction in terms of oxygen loss?

  Reduction is the loss of oxygen
• How can metals more reactive than carbon be extracted?

  By electrolysis
• How can metals less reactive than carbon be extracted?

  By reduction using carbon
• Which metal can be mined by itself?

  Gold
• What happens when acids and bases neutralize each other?

  • Produces salt and water
  • Acids release H+ ions
  • Alkalis release OH- ions
• What is the formula for neutralization of an acid and a base?

  Acid + Base → Salt + Water
• How do strong acids behave in water?

  They ionize completely
• How do weak acids behave in water?

  They do not fully ionize
• How does H+ ion concentration change with pH?

  Changes by $10^{-x}$
• What does concentration measure in a solution?

  Amount of acid in a certain volume
• What is produced when an acid reacts with a metal oxide or hydroxide?

  Salt and water
• What is produced when an acid reacts with metal carbonates?

  Salt, water, and CO2
• What occurs at the cathode during electrolysis?

  • H+ ions produce hydrogen gas if metal is more reactive than hydrogen
  • If not, pure metal is formed (e.g., copper)
• What occurs at the anode during electrolysis?

  • OH- ions and halide ions form molecules
  • If not, OH- ions discharge and oxygen is formed
• What does OILRIG stand for?

  Oxidation is loss, reduction is gain
• What is the reaction equation for iron and hydrogen ions?

  Fe + 2H⁺ → Fe²⁺ + H₂
• What happens to iron atoms in the reaction with hydrogen ions?

  Iron atoms lose electrons and are oxidized
• What happens to hydrogen atoms in the reaction with iron?

  Hydrogen atoms gain electrons and are reduced
• What is a displacement reaction?

  A more reactive metal displaces a less reactive metal
• What is the reaction equation for iron and copper sulfate?

  Fe + CuSO₄ → FeSO₄ + Cu
• What are the characteristics of cathodes and anodes?

  • Cathode: negative electrode, positive ions reduced
  • Anode: positive electrode, negative ions oxidized
• Why is cryolite mixed with aluminum oxide during extraction?

  To lower the melting point
• What is the reaction at the cathode during aluminum extraction?

  Al³⁺ + 3e⁻ → Al
• What is the reaction at the anode during aluminum extraction?

  2O²⁻ → O₂ + 4e⁻
• What are covalent bonds and their properties?

  • Strong bonds between non-metals
  • Form simple molecular substances (e.g., H₂, O₂)
  • Low melting and boiling points
  • Do not conduct electricity
• What are the characteristics of simple molecular substances?

  Strong covalent bonds, weak intermolecular forces
• What is ionic bonding?

  Bonding between metals and non-metals
• What is the formula for sodium chloride?

  NaCl
• What is the structure of ionic compounds?

  Giant ionic lattice with strong attractions
• Why do ionic compounds have high melting and boiling points?

  Due to strong electrostatic forces of attraction
• When can ionic compounds conduct electricity?

  Only when melted or dissolved in water
• What are the limitations of dot and cross diagrams?

  • Do not show arrangement of atoms
  • Do not represent 3D structure
• What are the limitations of displayed formulas?

  • Do not show arrangement of atoms
  • Do not represent 3D structure
• What are the limitations of ball and stick models?

  • Do not show where electrons bond
  • Can be confusing
• What is the formula for concentration?

  Concentration = mass of solute / volume of solvent
• How do you convert cm³ to dm³?

  Divide by 1000