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Material science - Coggle Diagram

- - - - VERY strong forces of attraction
        
        Particles are very close to one another
      - Arranged in a regular and orderly pattern
      - Vibrate about in a fixed position
      - Fixed volume & unable to flow
      - Incompressible
      - Very high density
      - Expands / contracts very little
    - - Strong forces of attraction
        
        Particles are close to one another
      - Arranged in an irregular and random pattern
      - Move about within the liquid
      - Fixed volume & able to flow
      - Incompressible
      - Density higher than gas but lower than solids
      - Expands / contracts more than solids but lesser than gases
      - Particles should touch one another
    - - VERY weak forces of attraction
        
        Particles are far apart
      - Arranged in an irregular and random pattern
      - Move freely
        
        All directions
        
        High speeds
      - No fixed volume & able to flow
      - Compressible
      - Low density
      - Expands / contracts greatly
  - - - Has fixed boiling points
    - - melt and boil over a range of temperatures
  - - - Thermal energy absorbed will be converted to kinetic energy so the particles vibrate faster as temperature increases
    - - Temperature does not change as the thermal energy absorbed is used to overcome forces of attraction between particles in a solid
  - - - Thermal energy is released to form strong forces of attraction between particles
    - - Thermal energy is released so kinetic energy decreases and particles move slower
- - - - Positively charged nucleus
        
        protons
        
        symbol: p
        
        relative mass: 1
        
        charge: +1 (positive)
        
        neutrons
        
        symbol: n
        
        relative mass: 1
        
        charge: 0 (neutral)
      - negatively charged electrons
        
        electrons
        
        symbol : e
        
        relative mass: 1 / 1837
        
        charge: -1 (negative)
  - - - affects how many electrons it can lose
      - determine chemical properties of an element
  - - - the number on top (14) refers to:
        
        nucleon number
        
        relative atomic mass
        
        mass number
        
        number of protons + number of electrons
      - number below (7) refers to:
        
        proton number
        
        atomic number
        
        number of protons
  - - - example:
        
        2,8,6
      - the numbers represent how many electrons there are in each shell, from innermost to outermost
    - - innermost shell max only 2 electrons
      - all subsequent shells have 1 to 8 electrons
      - Example: nitrogen has 2 electrons in its innermost shell and 5 in its valence shell
      - 2,6,7 is not possible, as the middle electron shell must be 8 for a new electron shell to be formed
    - - This is the diagram one where you have to draw stuff
  - - - remains the same
    - - due to different number of neutrons, its weight is different
    - - 2 extra neutrons
      - is an element of hydrogen
      - hydrogen-3 or H-3
    - - e.g. flourine doesnt have isotopes
        
        all atoms of flourine contain 10 neutrons and 9 protons
    - - is an unstable isotope
      - it undergoes radioactive decay
  - - - noble gases are unreactive due to their full valence shell
      - group I and group VII are relatively unstable, high energy, and reactive
        
        elements in group I only have one element to lose to gain a full valence shell
        
        elements in group VII only have one element to gain to get a full valence shell
      - When ions are formed, this causes the number of electrons to be of a different number than the protons
    - - metal ions (cation)
        
        lithium ion
        
        Li⁺
        
        Original: 2, 1
        
        sodium ion
        
        Sa⁺
        
        Original: 2, 8, 1
        
        potassium ion
        
        K⁺
        
        Original: 2, 8, 8, 1
        
        magnesium ion
        
        Mg²⁺
        
        Original: 2, 8, 2
        
        calcium ion
        
        Ca²⁺
        
        Original: 2, 8, 8, 2
        
        aluminium ion
        
        Al³⁺
        
        Original: 2, 8, 3
      - non-metal ions (anion)
        
        nitride ion
        
        N³⁻
        
        Original: 2, 5
        
        oxide ion
        
        O²⁻
        
        Original: 2, 6
        
        sulfide ion
        
        S²⁻
        
        Original: 2, 8, 6
        
        flouride ion
        
        F⁻
        
        Original: 2, 7
        
        chloride ion
        
        Cl⁻
        
        Original: 2, 8, 7
        
        bromide ion
        
        Br ⁻
        
        Original: 2, 8, 18, 7
        
        iodide ion
        
        I⁻
        
        Original: 2, 8, 18, 18, 7
    - - losing electrons
        
        Before:
        
        After:
      - gaining electrons
        
        Before:
        
        After:
- - - - Unreactive materials
        
        Copper
        
        Gold
        
        SIlver
  - - - Reversible
      - Only change in arrangements of atoms, not composition
    - - Chemical composition changes
      - Irreversible
  - - - Bubble the gas through limewater and if the limewater forms a white precipitate, carbon dioxide is present
    - - Fill a test tube with the gas and put a lighted splint in it, if the lighted splint relights, oxygen is present
    - - Fill test tube with gas and hover a burning splint over the test tube, if the burning splint extinguishes with a pop, hydrogen is present
  - - - found in food
      - examples:
        
        hydrochloric acid
        
        carbonic acid
        
        ethanoic acid
      - produces H⁺ ions when dissolved in water
      - Can conduct electricity
    - - are any metal oxide or metal hydroxide
        
        example
        
        sodium oxide
        
        aqueous ammonia / ammonium hidroxide
        
        potassium hydroxide
      - All alkalis are bases but not all bases are alkalis
    - - Can conduct electricity in solution
      - Have a soapy feel
      - substance that produces OH- ions when dissolved in water
      - Taste bitter
  - - - methyl orange
        
        Orange solution
        turns red/pink when tested with acid
        
        Orange solution
        turns yellow when tested with alkali
      - Phenolphthalein
        
        Remains colourless when tested with acid
        
        Turns pink when tested with alkali
      - universal indicator
        
        Green turns red when tested with acid
        
        green turns violet when tested with alkali
      - moist blue litmus paper
        
        REMAINS red when tested with acid
        
        Turns blue when tested with alkali
      - moist red litmus paper
        
        Turns red when tested with acid
        
        REMAINS blue when tested with alkali
- - - - Natural: cotton
        Manmade: Nylon (which are plastic)
        
        can be spun into threads and woven into fabrics
        
        can absorb dyes
    - - Made from petroleum
        
        strong, but light (as in low density)
        
        does not corrode easily
        
        poor conductors of heat and electricity
        
        can be moulded into shapes
    - - Made from sand
        
        transparent
        
        brittle
        
        poor conductor of heat and electricity
        
        does not corrode
        
        can be moulded into shapes
    - - Made from clay
        
        non-metallic solids
        
        hard but brittle
        
        high melting point
        
        poor conductors of heat and electricity
        
        does not corrode
    - - Extracted from the ground
        
        shiny
        
        good conductors of heat and electricity
        
        malleable and ductile
        
        some corrode while others do not
  - - - stronger
      - less brittle
      - different melting point
    - - more difficult for layers to slide over each other,
      - thus the alloy is harder than the pure metal
      - distorts the regular arrangements of atoms
    - - brass
        
        65% copper, 35% zinc
        
        Used in jewellery, machine bearings
      - bronze
        
        90% copper, 10% tin
        
        Used in machine parts
      - hard steel
        
        99% iron, 1% carbon
        
        cutting tools
      - stainless steel
        
        74% iron, 13% chromium, 8% nickel
        
        cutlery, surgical instruments
  - - - Glass-reinforced plastic
        
        short fibres of glass in plastic
      - Carbon fibre
        
        carbon and additives like polyester and aluminium
    - - strength
      - hardness
      - high ability to withstand heat
- - - - Filtration
        
        equipment
        
        filter funnel
        
        put on top of the conical flask
        
        filter paper
        
        put in the filter funnel
        
        conical flask
        
        used to contain the filtrate
        
        residue
        
        the remaining mixture
        
        filtrate
        
        the separated portion
        
        The large, insoluble particles cannot pass through the filter paper, which was collected as residue.
        
        The smaller, soluble particles pass through the filter paper and collect in the conical flask as the filtrate
      - magnetic attraction
        
        Used to separate magnetic materials from non-magnetic materials
        
        Magnetic materials
        
        CObalt
        
        Iron
        
        Nickel
        
        Steel
      - crystallisation
        
        Process
        
        Heat the substance and wait for the solution to become saturated. After that cool the solution and crystals shall form (TADAH)
        
        Saturation
        
        Saturation is the maximum amount of solute that can be dissolved in the solvent at a high temperature (I think)
      - evaporation to dryness
        
        basically making all the liquid in a solution evaporate/boil, leaving only the solid on the evaporating dish
        
        Equipment: (self-explanatory)
        
        wire gauze
        
        tripod stand
      - simple distillation
        
        The water evaporates from the flask and condenses in the Liebig condenser, bring water into the flask outside, being distillate
        
        equipment needed
        
        boiling chips
        
        liebig condenser
        
        distillation flask
      - fractional distillation
        
        Distillation but with glass beads in the top of the first flask which is called the fractionating column
        
        For substances with closer boiling points like ethanol (56 degrees boiling point) and Water (100 degree boiling point)
      - separating funnel
        
        If one of the liquids has a higher density than the other, you can put it in here
        
        There is a stopcock at the bottom that allows water to flow and not flow out
      - chromatography
        
        The solvent is usually water or ethanol
        
        Different substances travel different distances up the paper and sometimes have different colour, because of different solubility
        
        Draw the line with pencil so that when the pen ink is dissolved in the solvent you can still see the starting point
        
        starting line should be above the solvent
        
        Rf value = distance travelled by solvent / solvent front
      - Decanting
        
        used to separate a dense, insoluble solid from a liquid
        
        just pouring the liquid away, quite simple
      - Sublimation
        
        some liquids sublime when heated (change directly from solid to gas)
        
        iodine, dry ice, ammonium chloride
        
        First, the mixture is heated
        
        then iodine will sublime and deposit on the cooler surface of the inverted funnel as iodine crystals
        
        Equipment
        
        inverted funnel
        
        wire gauze
        
        evaporating dish
    - - Electrolysis
        
        process in which electricity flows through an electrolyte (a liquid) and decomposes it
        
        Example: Water
        
        split to form Hydrogen and Oxygen
      - thermal decomposition
        
        Causes a chemical change when a substance is broken down into simpler substances when heated
        
        Example: sugar
        
        sugar is broken down to form carbon + water vapour
  - - - pure substance
        (one substance)
        
        element
        
        compound
      - mixtures
        
        mixture of elements
        
        mixture of compounds
        
        mixture of elements and compounds
    - - Element
        
        its a PURE substance
        
        cannot be broken down into simpler substances by chemical processes
        
        characteristics
        
        can contain one or more atoms
      - Compound
        
        is also a PURE substance
        
        made up of 2 or more elements
        
        chemical combined together in a fixed ratio
        
        characteristics
        
        Properties of compounds differ from its constituent elements
        
        Examples:
        
        formed through chemical reaction
      - Mixtures
        
        They are not chemical combined together
        
        made up of two or more substances
        
        characteristics
        
        Mixtures are physically combined, and can therefore
        be physically separated.
        
        The method used depends on the properties of the
        substances in the mixture.
        
        Examples
        
        mixture of elements
        
        Alloys like bronze (Cu + Sn)
        
        mixture of compounds
        
        seawater (H2O + NaCl, etc)
        
        mixture of elements and compounds
        
        air (N2, O2, CO2, H2O, etc)
        
        No chemical reaction takes place when a mixture is
        formed.
        
        not in fixed ratio
        
        has properties of all its constituent elements
        
        solutions
        
        solvent - the liquid
        
        solute - the solid
        
        solution - the final product
        
        factors that affect rate of dissolving
        
        Temperature
        
        most solids dissolve faster at a
        higher temperature
        
        Surface area to volume ratio
        
        smaller pieces of a solid dissolve faster than large pieces.
        
        larger surface area to volume
        ratio in contact with the solvent
        
        Stirring
        
        solids dissolve faster when the
        solution is stirred
        
        suspensions
        
        A suspension is a mixture formed when one
        substance does not dissolve in a liquid
        
        examples
        
        orange juice
        
        medicines
        
        Comparison of suspensions and solutions
        
        suspensions
        
        particles are large
        
        1 more item...
        
        solutions
        
        particles are small
        
        1 more item...