Chemistry equations

Concentration

Concentration gdm3 \= mass / volume (dm3)

Convert cm3 to dm3

Divide by 1000

Number of moles in a substance

Number of moles \= mass (g) / R.F.M

empirical formula

a chemical formula showing the ratio of elements in a compound rather than the total number of atoms
-find number of moles and divide by smallest number

molecular formula

actual number of atoms
-find empirical mass and divide rfm by it

Avogadro constant

in 1 mole of a substance, there are 6.02 x 10^23 particles of the substance

Percentage yield

Actual yield/ theoretical yield x 100

theoretical yield

Add the R.F.M

Atom economy

R.F.M useful products / R.F.M of reactants x 100

Concentration in mol dm3

Number of moles in solute / volume of solute dm3

Concentration in mol dm3

Concentration gmd3 / r.f.m solute

Rf

distance substance travels from origin/ distance solvent travels from origin

Amount of gas mol

Vol of gas / molar vol (24dm3)

metal + water →

metal hydroxide + hydrogen

Metal + Acid

Salt + Hydrogen

ionic bond

Formed when one or more electrons are transferred from one atom to another, metal + non metal
Do not conduct as solid but as liquid or dissolved conduct
High melting point: strong electrostatic bonds between ions
Soluble in water: water molecules slight electrical charge, attracting ions away from the lattice

covalent bond

a bond formed when atoms share one or more pairs of electrons, non metal + non metal
Molecular solids: low melting ans boiling points however larger solid stronger molecular forces

Graphite

Only three out of four electrons in carbon involved so can conduct electricity and soft and slippery, lube, malleable

Diamond

Massive covalent
High melting + boiling
Can't conduct electricity
V hard

metallic bonding

a bond formed by the attraction between positively charged metal ions and the electrons around them, giant lattice w delocalised electrons\=conduct
Malléable: sea of electrons slide over each other
High melting point: string bonds

Smart alloy

Metal that changes shape depending on temperature

Allotrope

Different structural forms of the same element

What is pH?

the measure of the hydrogen ion concentration in a solution. If you decrease the concentration of H+ ions by a factor of 10 the ph increase by 1

Strong acids

Fully dissociate into H+ ions

Acid + Base

Salt + Water

Acid + Carbonate

Salt + Water + Carbon Dioxide

concentrated solution

a solution containing a large amount of solute dissolved in small amount of solvent

Bases

Bases neutralise acids. They are hydrogen ion acceptors. When they react, they accept H+ions.

Acids

Acids are hydrogen ion donors. When they react, they release H+ ion(s).

soluble in water

sodium, potassium, and ammonium compounds, nitrates, MOST chlorides, MOST sulfates

insoluble in water

Silver lead carbonates, lead barium calcium sulfate, MOST carbonates, MOST hydroxides

Reactivity series

Potassium
sodium
calcium
magnesium
aluminium
Carbon
zinc
iron
lead
Hydrogen
copper
silver
gold

Anodes

Electrodes where oxidation occurs, anions (negative ions) go, positive, non metals, oxygen forms

Cathode

Reduction, negative, cations (positive ions) go, metals, hydrogen forms

Ore

a rock that contains a large enough concentration of a mineral making it profitable to mine

METHODS OF EXTRACTION

Higher than carbon: electrolysis
Lower than carbon: displacement reaction with carbon

Bioleaching

Process of extraction of metals from ores using microorganisms. Bacteria produce solution called a leachate where copper extracted via displacement and purified by electrolysis

Phytoextraction

The process by with plants exact metals from soil or water and store them above ground. Burnt to get the element

Equilibrium

Increase of temperature exothermic direction (to the right)
Increases of pressure favours reaction which produces less moles (to the right)

Haber process

450 dégrées, 200 atmosphères, iron catalyst

Properties of transition metals

-malleable -good conductors of electricity -high melting points

• high densities

• typically show catalytic activity

Fermentation Advantages

-made from renewable carbohydrates
-lower temperature
-low pressure
HOWEVER ITS SLOW AND PRODUCT IS IMPURE

Properties of alkali metals

-malleable
-conduct electricity
-low melting points
-very reactive

Properties of halogens

-non metallic
-poor conductors of heat and electricity
-toxic and corrosive

Properties of noble gasses

-colourless
-low melting and boiling points
-poor conductors of heat and electricity

Metal properties

Shiny, malleable, ductile, conductive, and sometimes magnetism

Non metal properties

Low melting points
Not shiny
Brittle
Low density
Poor conductors of electricity

Insoluble in water

-silver, lead chloride
-lead, barium, calcium sulfates
-most carbonates
-most hydroxides

Water for drinking treatment

-sedimentation tank
-filtration tower including sand and gravel
-chlorination which kills micro organisms

Calculate r.a.m from abundances

Total mass of the atoms / number of atoms

R.A.M

The mean mass of an atom of an element compared with carbon-12

Mendeleev's periodic table

Organized by 3 criteria: 1- atomic mass 2- reactivity and 3- formula

-ide ending

In two element compounds the non-metal ends in ide

polyatomic ion

an ion made of two or more atoms
If it contains oxygen it ends in -ate or -ite

Neutralisation reaction

Acid + base \= salt + water

Polymer

A long molecule consisting of many similar or identical monomers linked together.

Fullerene

A molecule in which each carbon atom is covalently bonded to three other carbon atoms, forming tubes or spheres

functional group

Group of Atoms that is responsible fir te molecules chemical reactions and properties

fuel cell

A device that converts chemical energy to electrical energy.

Homologous series

same general formula and similar chemical properties but different number of carbon atoms

Halide ion

Negatively charged ion formed from one of the group 7 elements

Nanoparticle

Tiny pieces of a substance with a diameter between 1 nanometre and 100 nanometres

Alkaline tests

Litmus: blue
Methyl orange: yellow
Phenolphthalein: pink

Acid tests

Litmus: red
Methyl Orange: red
Phenolphthalein: colourless

Fractions of crude oil

Gases
Petrol
Kerosene: fuel for aircraft
Diesel
Fuel
Bitumen: surfacing roads

Properties of fractions of crude oil

Top: small carbons, low boiling point, easy to ignite, flows easy

Alkanes

CnH2n+2
React with oxygen to form carbon dioxide + water

Complete combustion

Only oxygen and water are given out and energy is produced
If not carbon monoxide is produced

Hydrocarbon pollutants

Car engines 'internal combustion' and oxides of nitrogen are produced
Contain impurities such as carbon

Saturated

Carbon atoms are joined only be C-C

Cracking

Large alkane molecules split into alkane and alkane

Alkenes

CnH2n
Unsaturated

Isomers

Molecules with the same molecular formula but different arrangements of atoms

Bromine water test

Alkanes do not cause de-colourisation

Alcohols

CnH2n+1
Have the functional group OH
Produce oxygen and water on complete combustion
Can be oxidised to form carbolyxic acids
React with sodium

carboxlyic acid

CnH2n+1 COOH
FORM ACIDIC solutions

carboxlyic acid + metal

\= salt + hydrogen

carboxlyic acid + base

\= salt + water

carboxlyic acid + carbonates

\= salt + water + carbon dioxide

Poly (ethene)

Flexible, cheap
Plastic bags

Poly (propène)

Flexible, does not shatter

Poly (chloroethene) PVC

tough, hard
Window frames

PTFE (teflon)

Tough, slippery
Non stick pans

condensation polymerization

2 monomers react to form a larger unit while a small molecule, water is the by product

Flame tests

Wire loop dipped in HCL before testing each sample

Lithium

Red
Li+

Sodium

Yellow
N'a+

Potassium

Lilac
K+

Calcium

Orange-red
Ca2+

Copper

Blue/green
CU2+

Sodium Hydroxide tests

Test for metal precipitation reaction

Iron

Fe2+ \= green
Fe3+ \= Brown

Copper

Cu2+ \= blue

Calcium, aluminium

Ca2+, Al3+ \= white

Ammonium test

Damp red litmus paper blue

Carbonate ions test

Add HCL to substance and see if lime water goes cloudy

Sulfate ions test

Add HCL to remove carbon ions and than add barium chloride to give white precipitate

Halide ion test

Add nitric acid to remove carbon atoms and add silver nitrate to see precipitate (white Cl-, cream Br-, yellow I-)

composite material

A material with two or more materials combined to produce a material with improved properties

matrix material

In a composite material, the substance that binds the reinforcement material together