C1 Atomic Structure and the Periodic Table

• What are the main topics covered in section 4.1.1?

  • Model of atoms
  • Atoms, elements, and compounds
  • Mixtures
  • Relative electrical charge of subatomic particles
  • Size and mass of atoms
  • Relative atomic mass
  • Electronic structure
• What is an atom?

  An atom is the smallest part of a substance that can exist.
• What is an element?

  An element is a substance made up of just one type of atom.
• How many different elements are there approximately?

  About 100 different elements.
• How can atoms be represented?

  Atoms can be represented by chemical symbols.
• What is a compound?

  A compound contains two or more different types of elements chemically bonded together.
• What happens to the properties of elements when they form a compound?

  The properties of a compound are usually totally different from the properties of the elements that make it up.
• What are the methods to separate mixtures?

  • Filtration
  • Crystallisation
  • Simple distillation
  • Fractional distillation
  • Chromatography
• What is the definition of a mixture?

  A mixture consists of two or more elements or compounds not chemically bonded together.
• What is the significance of the chemical properties of substances in a mixture?

  The chemical properties of each substance in the mixture remain unchanged.
• What is the keyword for the process of separating a liquid from undissolved solids?

  Filtration
• What does a formula show in chemistry?

  A formula shows what elements are present in a compound and how many atoms of each element it contains.
• How do you name a compound with two types of atoms?

  You use the suffix "-ide" for compounds with only two types of atoms.
• What is the conservation of mass in a chemical reaction?

  The total mass at the start of the reaction equals the total mass at the end.
• What are the steps to separate a mixture of sand and salt?

  1. Dissolve the salt in water.
  2. Filter the mixture to remove sand.
  3. Evaporate the water to obtain pure salt.
• What is the purpose of chromatography?

  Chromatography is used to separate mixtures based on their different solubilities.
• What is the role of a solvent in a solution?

  A solvent is a liquid that can dissolve a solid to make a solution.
• What happens during a chemical reaction?

  New substances are formed during a chemical reaction.
• What are the differences between elements, compounds, and mixtures?

  • Elements: Pure substances made of one type of atom.
  • Compounds: Substances made of two or more different types of atoms chemically bonded.
  • Mixtures: Combinations of two or more substances that are not chemically bonded.
• What is the chemical formula for water?

  H₂O
• What is the chemical formula for carbon dioxide?

  CO₂
• What is the chemical formula for sodium chloride?

  NaCl
• What is the chemical formula for magnesium oxide?

  MgO
• What is the chemical formula for sulfur dioxide?

  SO₂
• What is the chemical formula for glucose?

  C₆H₁₂O₆
• What is the chemical formula for calcium hydroxide?

  Ca(OH)₂
• What is the chemical formula for beryllium chloride?

  BeCl₂
• What is the chemical formula for copper sulfate?

  CuSO₄
• What is the chemical formula for lithium bromide?

  LiBr
• What is the chemical formula for calcium carbonate?

  CaCO₃
• What is the chemical formula for silver oxide?

  Ag₂O
• What is the chemical formula for silver bromide?

  AgBr
• What is the chemical formula for hydrochloric acid?

  HCl
• What is the chemical formula for sulfuric acid?

  H₂SO₄
• What is the chemical formula for nitric acid?

  HNO₃
• What are the steps to write a balanced symbol equation?

  1. Write the unbalanced equation.
  2. Count the number of atoms of each element.
  3. Adjust coefficients to balance the atoms.
  4. Ensure the same number of each type of atom on both sides.
• How can you tell if a chemical reaction has occurred?

  New substances are formed, and there may be observable changes like color change or gas production.
• What are the properties of iron and sulfur?

  • Iron: Grey solid metal, magnetic, dense.
  • Sulfur: Yellow non-metal, solid.
• What are the properties of water?

  • Water: Liquid at room temperature, essential for life, solvent for many substances.
• What is the importance of the periodic table?

  • Organizes all known elements.
  • Provides information on atomic structure and properties.
  • Helps predict chemical behavior.