Please enable JavaScript.

Coggle requires JavaScript to display documents.

Science, Terminal Velocity, Atmosphere, C8 (Gas tests, Chromatography,…

- - - - Group 1: Alkali Metals:
      - Very reactive metals.
      - React vigorously with water, producing hydrogen gas and metal hydroxides.
      - Reactivity increases down the group.
    - - Group 7: Halogens:
      - Reactive non-metals.
      - Reactivity decreases down the group.
      - Form negative ions (halide ions).
    - - Group 0/8: Noble Gases:
      - Inert (unreactive) gases.
      - Have a full outer shell of electrons.
    - - Organization: Elements are arranged in order of increasing atomic number.
      - Periods: Horizontal rows.
      - Show the number of electron shells.
      - Groups: Vertical columns.
      - Show the number of electrons in the outer shell (valence electrons).
      - Elements in the same group have similar chemical properties.
      - Metals and Non-metals:
      - Left side of the periodic table: Metals.
      - Right side of the periodic table: Non-metals.
      - The dividing line is the staircase line.
    - - Chromatography (Paper Chromatography):
        
        Principle: Separates dissolved substances based on their differing solubilities in a solvent and their differing attractions to the paper.
        
        Method: A spot of the mixture is placed on filter paper, and the paper is placed in a solvent. The solvent travels up the paper, carrying the dissolved substances with it. Substances with higher solubility and lower attraction to the paper travel further.
        
        Simple Distillation:
        
        Principle: Separates a liquid from a solution (or two liquids with significantly different boiling points).
        
        Method: The solution is heated, and the liquid with the lower boiling point evaporates. The vapour is then cooled and condensed back into a liquid.
        
        Examples: Separating pure water from saltwater.
        
        Fractional Distillation:
        
        Principle: Separates a mixture of miscible liquids with different boiling points.
        
        Method: The mixture is heated, and the vapours pass through a fractionating column. Liquids with lower boiling points evaporate and condense higher up the column. The fractionating column allows for repeated evaporation and condensation, leading to better separation.
        
        Examples: Separating crude oil into its different fractions (e.g., petrol, kerosene).
        
        Filtration:
        
        Principle: Separates an insoluble solid from a liquid.
        
        Method: The mixture is poured through filter paper in a funnel. The solid (residue) is trapped by the filter paper, while the liquid (filtrate) passes through.
        
        Examples: Separating sand from water, removing solid impurities from a liquid.
        
        Filtration:
        
        Principle: Separates an insoluble solid from a liquid.
        
        Method: The mixture is poured through filter paper in a funnel. The solid (residue) is trapped by the filter paper, while the liquid (filtrate) passes through.
        
        Examples: Separating sand from water, removing solid impurities from a liquid.
        
        Crystallisation:
        
        Principle: Separates a soluble solid from a solution.
        
        Method: The solution is heated to evaporate some of the solvent, creating a saturated solution. Upon cooling, the dissolved solid crystallises out.
        
        Examples: Obtaining pure crystals of copper(II) sulfate from its solution, obtaining sugar from sugar cane juice.
  - - - Metal + Non Metal
      - Transfer of Electrons
      - Lithium (Li) Loses an electron rather than gain 7 to become a positive ion
      - Chlorine (Cl) gains one electron rather then lose 7 to become a negative ion
- - - - Energy Stores: Kinetic, thermal, gravitational potential, elastic potential, chemical, magnetic, electrostatic, nuclear.
        
        Energy Transfer: Energy can be transferred by heating, light, sound, electrical work, mechanical work.
        
        Closed Systems: The net change in the total energy of a closed system is always zero. Energy can be transferred between stores within the system.
        
        Conservation of Energy
        
        Principle of Conservation of Energy: Energy cannot be created or destroyed, only transferred from one store to another.
        
        Wasted Energy: In any energy transfer, some energy is always dissipated (spreads out) into less useful forms, usually thermal energy.
        
        Energy and Work
        
        Work Done: When a force causes an object to move, energy is transferred.
        
        Work done (J) = Force (N) × Distance (m)
        
        Gravitational Potential Energy (GPE)
        
        Energy stored in an object due to its position above the Earth's surface.
        
        Gravitational Potential Energy (J) = mass (kg) × gravitational field strength (N/kg) × height (m)
        
        Energy Dissipation
        
        Energy is often lost to the surroundings as heat due to friction or air resistance.
        
        Methods to reduce unwanted energy transfer: lubrication (reduces friction), insulation (reduces heat loss).
        
        Electrical Appliances
        
        Energy transfers in common appliances (e.g., kettle, motor, light bulb).
        
        Power (W) = Energy transferred (J) / Time (s)
        
        Energy Resources
        
        Renewable Resources: Can be replenished (e.g., solar, wind, hydro, geothermal, biomass).
        
        Non-Renewable Resources: Cannot be replenished at the rate they are used (e.g., fossil fuels, nuclear fuels).
        
        Environmental Impacts: Consider the environmental effects of different energy resources.
  - - - Static Electricity
      - Electric Charge: Positive and negative charges. Like charges repel, opposite charges attract.
      - Insulators and Conductors: Insulators do not allow charge to flow easily, conductors do.
      - Charging by Friction: Transfer of electrons between insulating materials.
      - Electrostatic Phenomena: Sparks, shocks, attraction of small objects.
      - Electric Fields: Region around a charged object where another charged object experiences a force. Field lines show the direction of the force on a positive charge.
  - - - Longitudinal
      - Transverse
- - - - Cytoplasm: Where chemical reactions occur.
        
        Cell membrane: Controls entry/exit of substances.
        
        Mitochondria: Respiration.
        
        Ribosomes: Protein synthesis.
        
        Cell wall: Support (cellulose).
        
        Vacuole: Stores cell sap.
        
        1 more item...
    - - Examples: Red blood cells, nerve cells, sperm cells, muscle cells, root hair cells.
    - - Lack a true nucleus, contain plasmids, cell wall.
  - - - Enzymes (Core Concepts)
      - Definition: Biological catalysts that speed up reactions.
      - Structure: They are proteins.
    - - Action:
      - They have a specific area called the active site.
      - The molecule they act on (the substrate) fits into the active site (Lock and Key model).
      - They are specific (each enzyme acts on only one substrate).
    - - Stomach: Produces HcL acid (kills bacteria, provides optimum $\text{pH}$ for pepsin) and Protease.
      - Pancreas: Releases all three enzyme types (Amylase, Protease, Lipase) into the small intestine.
      - Small Intestine: Main site for both chemical breakdown and absorption.
        Villi: Structures that increase surface area for efficient absorption into the blood.
      - Large Intestine: Absorbs water.
      - Bile
        
        Made in: Liver.
        Released into: Small Intestine
- - - - First oceans (Rained for a long time)
        
        CO2 was able to dissolve into the new oceans forming carbonate precipitates (E.g. Limestone)
        
        First Algae evolve and photosythesis
        
        Oxygen starts to be released
        
        More complex live evolves (Trees)
        
        Shelled animals evolve