My notes

• Matter


  Anything that has a mass and occupies space
• Matter


  • Water
  • Fire
• Not matter


  • Feelings
  • Sounds
• Intermolecular attraction


  The force by which the molecules of solid, liquid and gas are attached to each other strongly
• Solid matter


  • Has a mass, volume and shape
  • Examples: table, ice, metal
• Liquid matter


  • Has a specific mass and volume but no fixed shape
  • Examples: water, blood, gasoline, wine, milk
• ARUS


  2023
• Chemical Reactions


  The change which causes a substance to get a new set of properties giving own properties and features is called a chemical change. The process that brings the change is called a chemical reaction.
• Chemical equation


  Expression of a chemical process by using symbols, formula and sign.
• Reactants


  The substances that are used to begin a chemical reaction
• Products


  The substance or substances with new properties that are formed at the end of the reaction
• Rules to write chemical equations

  1. Reactants on left, products on right, equal sign or arrow in middle

  2. Reactants and products written using symbols and formulas, plus sign if multiple

  3. Number of atoms of different elements on left and right side need to be equal (balancing)

  4. Unbalanced equations use arrow instead of equal sign

  5. Physical states of reactants and products can be mentioned in brackets (s, l, g)

  6. If an element appears on both sides, it is not necessary to write it twice
• Some reactions are written with a delta (Δ) symbol to indicate they require heat energy
• Balancing chemical reactions


  Equalizing the number of atoms of different elements on the left and right side of the equation