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Chapter 1: Atomic structure (1)

All atoms are made up of 3 things: Neutrons, Protons and Electrons

  • Neutrons: Reletive charge:0 Reletive Mass:1
  • Protons: Reletive charge: +1 Reletive Mass: 1
  • Electrons: Reletive cherge: -1 Reletive Mass: 1/1836

Atomic number = number of p[rotons

Mass number = number of protons + number of neutrons

Number of electrons = number of protons

Isotopes are atoms which have the same atomic number, but different mass number. They have the same number of protons, but diferent number of neutrons. Electrons are aranged into energy levels. There are 2 alowed in the 1st anergy level, 8 in the 2nd and 18 in the 3rd.

  • The number of electrons in the outer level is the same as the group number for groups 1 to 7.
  • The elenents in group 0 have 8 electrons in their outer levels.
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Chapter 1: Atomic structure (2)

  • The number of electrons in the outer level is the same as the group number for groups 1 to 7.
  • The elenents in group 0 have 8 electrons in their outer levels.
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Chapter 2: States of Matter

There are 3 states of matter: Solid, liquid and gas.

Solid to Liquid = Melting, Solid to Gas = Sublimation, Liquid to Solid = Frezing, Liquid to Gas = Evaperation, Gas to Liquid = Condensation.

  • Diffusion: the process in which there is movement of a substance from an area of high concentration of that substance to an area of lower concentration.
  • Brownian motion: the random motion of small particles suspended in a gas or liquid.
  • Dilution: weakening (reducing the concentration) by the addition of water or a thinner.
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Chapter 3: Bonding

Convalent bonding: in convalent bonding a pair of electrons is shared between two atoms. Each of the positively charged nuclei is attracted to a negitively charged pair of electrons.

Ionic bonding: is the bonding in which there has been a trnsfer of electrons from one atom to another to produce an ion.

An ion is an atom which carries an electrical charge, either posotive of negetive.

  • A posotive ion is called a cation.
  • A negtively charged ion ic called an anion.

Metallic bonding: is the electromagnetic interaction between delocalized electrons, called condution electrons, and the metallic nuclei within metals. Understood as the sharing of "free" electrons among a lattice of positively-charged ions (cations).

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Chapter 4: Structure

Giant structure: Is a Large numbers of atoms/molecules arranged in a regular way.

Giant metalic structure: the metal is held together by the attractions between the posotive ions and the delcalised electrons.

Alloys: An alloy is a mixture of metals.

Giant ionic structure: All ionic compounds consist of huge lattices of posotive and negetive ions packed together in a regular way. A latice is a regular array of particles. The lattice is held together by the strong attractions between the posotively and negetively charged ions.

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Chapter 5: Seperating mixtures (2)

Crystillisation: impure mixture is first dissolved in the warm solvent. As the temperature falls, the material becomes less soluble and the more abundant material then crystallises out. The impurity remains in the solution. If the impurity is insoluble, it can be removed by filtretion.

Filtration: Pouring a mixture of water with sand through filer paper, the large particle will get left behind.

Simple distillation: Distillation seperates mixtures of liquids. Water boils at 100 degrees C but ink boils at a differetn temperature, much heigher. We can distil pure water from inky water this way.

Fractional distillation: it is the same proses of simple distillation but containing alot more liquids so there are a lot more stages of boiling the liquids.

Paper Chromotography: We use this to seperate small amounts of mixed colour.

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Chapter 5: Seperating mixtures (1)

Elements: Are substances which can't be split into anything more by chemical means. All the atoms in the element have the same atomic number.

Compounds: All compounds are made from combinations of two or more elements in fixed proportions, and joined by strong bonds.

Mixtures: is were there is a mixture of compounds and they can be in any proportion.

Solution: a solution is formed when a substance dissolves in a liquid. The solution becomes a staurated solution when i contains as much disolved solute as posible at a particular temperature.

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Chapter 6: Formulae and Equations

How to balance equations: work accros the equation from left to right, checking one element after another, except if an element appears in several places in the equation. In that case, leave it until the end - you will often find that the numbers will then be balanced. If you have a group of atoms which is unchanged from one side of the equation to the other, count that up as a whole group.

State symbols: (s) solid, (l) Liquid, (g) gas, (aq) in aqueous solution.

Elements in periodic group:Charge on ion

  • 1 +1
  • 2 +2
  • 3 +3
  • 6 -1
  • 7 -2
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Chapter 7/8: Reletive Atomic Masses and Moles + Ca

The reletive atomic mass (Ar) of an element is the weighted average mas of the isotopes of the element. It is measured on a scale on which a carbon - 12 atom has a mass of exactly 12 units.

The weighted average is worked out by doing:

  • times the Relative atomic mass of the atom and timesing it by its Persentage you do this for all the atoms present and add them together. Then you divide by 100. This gives you the weighted average.

The Reletive formula mass (Mr) is just adding the reletive atomic masses and this gives you the Reletive formular mass.

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Chapter 7/8: Reletive Atomic Masses and Moles + Ca

To find the percentage by mass we find the reletive formular mass of the whole thing. Then we take the reletive atomic mas for the atom we want the percentage of and divide it by our reletive formular mass. Then we times it all by 100, this gives you the percentage of the that atom.

To find the mass of 1 mole of a substance we work out the reletive formular mass and simply put grams on the end.

number of moles= mass(g)/mass of 1 mole

empirical formula is you take the number from the text the combining masses and divide them by the Atomic mass relevent to that atom and this will leave you with a number for each of the atoms and this emables you to see the ratio that they work together in.

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Chapter 9: The Ractivity Series

Potassium, Sodium, Lithium, Calcium, Magnesium, Aluminium, (Carbon), Zinc, Iron, Tin, Lead, (Hydrogen), Copper, Silver, Gold, Platinum.

  • A substance has been oxsidised if it gains oxygen
  • A substance has been reduced if it loses oxygen.

A redox reaction is one which does both reduction and oxidation.

A reducing agent is a substance which reduces something elss.

A oxidising agent is a substance which oxidises something else.

  • metal + cold water ---> metal hydroxide + hydrogen
  • metal + steam ---> metal oxide + hydrogen
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Chapter 10: Acid bases and PH

  • PH scale: 0 -6 acidic, 7 neutral, 8 - 14 alkalne.
  • simple indicators: acidic = red, neutral = purple, alkaline - blue.

indicators colour in acid colour in alkali

  • litmus red blue
  • methyl orange red yellow
  • phenolphthalein colourless red
  • universal red purple

metal + acid ---> salt + hydrogen, metal oxide + acid ---> salt + water, metal hydroxide + acid ---> salt + water, carbonate + acid ---> salt + carbon dioxide + water, any ammonium salt + base ---> ammonia gas.

  • an acid is a proton (hydrogen ion) donor
  • a base is a proton (hydrogen ion) acceptor
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Chapter 11: Making Salts

All sodium, potasium and amonium compounds **** soluble, all nitrates are soluble, all common ethanoates (also called acetates) are soluble. Most common chlorides are soluble, except lead (II) chloride and silver chloride. Most common sulphates are soluble, except lead (II) sulphate, barium sulphate and calcium sulphate. Most common carbonates are insoluble, except sodium, potassium and ammonium carbonates. Most metal hydroxides are insoluble (or almost insoluble), except sodium, potasium and amonium hydroxide.

To make soluble salts:

  • acid + matal (but only moderatly reactive metals from magnesium to iron in the reactivity series)
  • acid + metal oxide or hydroxide
  • acid + carbonate
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Chapter 11: Making Salts

Summarising methods of making salts:

  • To make a anhydrous chloride - Heat the metal in a dry chlorine
  • To make a soluble salt - Use a precipitation method. Mix two solutions, one containing the corect posotive ion and the other the corect negative ion.
  • To make a sodium, potasium or ammonium salt - Use a titration method. React an acid with a solution of sodium or potasium hydroxide or carbonate (or use amonium solution).
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Chapter 12: Titration calculation


  • Write down everything you know. Placing the one you know most about on the left (you don’t have to do this, but its just a good idea).
  • Write the equation or as much as you know about it. This is necessary to check out the ratios of reactants
  • Calculate the Number of Moles used of the reactant you know most about. In this case the HCl(aq)
  • The rule here is Number of Moles = (volume/1000) × concentration
  • Work out the concentration of the potassium hydroxide.

number of moles= mass(g)/mass of 1 mole (g)

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Chapter 13: Rates of reaction

Rate is a measure of speed that a reaction takes place at. The rate changes throuhgout the reaction. The rate is greatest at the start, but gets less as the reaction proceeds. Rate of reaction can be changed by:

  • Change in concentration
  • Change in temperature
  • Change in surface area and reactants
  • Use of a ctalyst

A catalyst is a substance that changes the rate of a chemical reaction but remains chemically unchanged.

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Chapter 14: Energy Changes in Reactions

When bonds break, energy must be absorbed from their surroundings. Taking in energy reduces the temperature of the surroundings - this is called an endothermic reaction. This value is always given a positive sign, for example, +345kJ. When bonds are made, energy is released to the surroundings. Energy that is released to the surroundings is called an exothermic reaction. This value is always given a negative value, for example, -345kJ. Remember, when a reaction takes place bonds break (endothermic) then bonds are made (exothermic).Overall, the reaction will be exothermic if more energy is released into the surroundings than was absorbed.An endothermic reaction will occur overall if, more energy is absorbed from the surroundings than is released.

Bond energy: This is the energy required to break one mole of bonds. The bond energy is also the energy given out when a mole of bonds is formed.

Activation energy: This is the minimum amount of energy required to break bonds to start the reaction off.

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Chapter 15/16: Industrial Chemistry and Reversible

There are several types of reaction:

  • Combination.
  • Decomposition.
  • Fermentation.
  • Precipitation.
  • Electrolysis.
  • Neutralisation.
  • Redox.
  • Combustion.

When a chemical reaction occurs, bonds are broken and then made. Breaking bonds requires energy to be taken in. Bond making releases energy. Bond energy is the energy required to break one mole of bonds, measured in kilojoules. It is also the energy given out when bonds are broken.

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Chapter 17: Electrolysis Calculations

The coulomb is a measure of quantity of electricity. 1 coulomb is the quantity of electricity which passes if 1 ampere (amp) flows for 1 second

number of coulombs = current in amps x time in seconds

A flow of electricity is a flow of electrons. 1 faraday is the quantity of electricity which represents 1 mole of electrons passing a particular point in the circuit - in other words, approximately 6 x 1023 electrons.

1 faraday = 96 500 coulombs (or approximately 96000 c)

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