chemistry core

a substance with low melting point

measuring accurate whole fixed numbers

increases boiling point and decreases melting point

random movement of gas particles due to collisions

• ethanol (C2H5OH)
• acetone (C3H6O)

by using a hot water bath

• calcium hydroxide
• Ca(OH)2

filtration

• simple distillation
• -heat solution of salt and water
• -water will evaporate and go into the condenser
• -water cools and condenses 
• -water falls into beaker leaving salt crystals behind

• -by crystalization
• -slightly heat solution until it is saturated
• -cool solution until copper sulfate fall from water
• -filter water from copper sulfate

• -add ethanol and stir until sugar has dissolved 
• -filter separating salt from sugar and ethanol
• -evaporate ethanol so sugar crystals remain behind

gloss paint

• -glue
• -perfume

• nail polish 
• grease

• -by separating funnel
• -pour mixture
• -wait until they separate
• -open the tap and lower layer will drip
• -close tap when lower layer is all in the beaker

• -by  fractional distillation
• -heat solution until 78 degrees
• -ethanol will boil and go through the fractionating column then through the condenser
• -it cools and condenses and falls into the receiving flask
• -some of the water will evaporate and go into fractionating column where it will hit the glass beads
• -cool and condense ad fall back into the distilling flask

• -by paper cromatography
• -draw a line in pencil (origin line) 
• -add coloured substance on the origin line 
• -put the paper in a solvent the solvent should reach to just bellow the origin line
• -water will diffuse up the paper until nearly the end of the paper 
• - remove the paper from the solvent and colour mixture shpuld be separated

as  graphite is insoluble in most solvents

in order for the substances to diffuse up the paper and and not dissolve in the beaker

isotopes with unstable nucleus

-energy in nuclear power station

to detect leaks in oil tanks

• sterilizing hospitals
• radiotherapy
• surgical tools

• uranium
• francium 
• cobalt- 60

Ionic bonds

a substance that is charged due to losing or gaining electrons

covalent bond

atom of the same element with same number of protons but different number of neutrons

an atom of the same element with the same chemical properties but different physical properties

sodium and potassium

• metal=good
• non metal =poor
• simple covalent= poor
• ionic=good when dissolved or melted 
• giant covalent= graphite =good

• metals=insoluble
• non metals=insoluble
• ionic=mostly soluble
• simple covalent =mostly insoluble
• giant covalent = insoluble

• metals= high
• non metals= low
• ionic=high
• simple covalent= low
• giant covalent=high

due to having a flat hexagonal structure that slide over each other

due to every  carbon atom having 3 covalent structures leaving 1 electron freely moving and being a good conductor of electricity

due to each carbon atom having 4 covalent bonds in a tetrahedral structure making it very hard

to overcome the forces between each carbon atom in the tetrahedral structure

• neutralize using alkali
• -limestone CaCO3
• -Slaked Lime Ca(OH)
• -Quick Lime CaO

toothpaste

• -making plastic
• -liquid bleach
• -purifying water

• -cars 
• -Nails
• -Tin coated cans

-making wires

-space rockets

teat pipette

-irreacative

• -gas syringe
• -burette
• -inverted measuring cylinder

• oxidation = gain of oxygen 
• reduction = loss of oxygen

• Ar relative atomic mass for atoms 
• Mr relative molecular mass for molecules or compounds

crystal lattice

• F--> green 
• Cl ---> yellow
• Br ---> reddish brown
• I ---> Black

• F ---> yellow
• Cl ---> green 
• Br --red orange 
• I --->purple(G) grey(s) brown (aq)
• At ---> Black

• They all produce metal hydroxide and hydrogen 
• Li --> fizzes 
• Na ---> shoots across 
• K ---> catches fire

• H ---> hot air balloon (irreactive and low density)
• Ne ---> flourescent light advertisment (lights up when electricity passes through)
• Ar ---> light bulb/welding (creates innert enviroment)
• Kr --->laser eye surgery / light in cars
• Xe ---> ligh in cars

-photographic chemicals

the breakdown of ionic bond using electricity

• test: glowing splint
• result: relights

• test: lighted splint 
• result: goes off

• test: lighted splint
• result: squeezing POP sound

• test: Potassium permenganate 
• result: bleaches

• test: damp litmus paper 
• result: bleaches

• test: damp red litmus paper 
• result: turns blue

• -used in alloys
• -used as catalysts
• -form coloured compounds
• -have more than 1 valency

a compound that loses O2 so another one can gain

a compound that gains O2 so another one can lose

• -add steel plate at the cathode 
• -add pure Ag to anode
• -use AgNO3 as electrolyte 
• -it breaks into Ag+ and NO3- 
• -Ag+ goes to cathode, gains electrons and forms a shiny layer of metal on the plate
• -NO3 goes to anode reacts with Ag forming AgNO3 that will break into Ag+ and NO3- repeating the process again
• -cathode gets thicker 
• -anode gets thinner

• -for a less reactive layer 
• -for a shiny appearance

the coverage of an object with a layer of usually less reactive metal

• H+ always wins at cathode except if (Cu, Ag, Au)
• O-  always wins at anode except if concentrated and G7

• +ions = cathode which is the negative
• -ions = anode which is the positive

Bauxite

• -add graphite as electrodes 
• -add Al2O3 as electrolyte 
• -it will break into Al+ and O3-
• -Al+ will go to cathode and gain electrons and become Al  
• -O- will go to anode and react with  the C as the temperature will have broken the hexagonal structure  producing CO2 gas

how an element is found in nature

• -irreactive
• -good conductor 
• -high mp

• -metal+ acid --->salt + hydrogen 
• -metal oxide + acid ----> salt + water
• -metal hydroxide + acid ---> salt + water
• -metal carbonate +acid --->salt +water +carbon dioxide
• -metal hydroxide + ammonium....... ----> salt +water + ammonia

• -add MgO to water and stir to dissolve 
• - litmus paper turns blue

• -litmus = blue
• -methyl orange = yellow
• -phph = pink

• -litmus = red
• -methyl orange = red
• -phph = colourless

• BY ADDING WATER to a 
• -weak acid = partial disassociation of H = low conc of H+ions
• -strong acid = total disassociation of H = high conc of H+ ions
• -weak alkali = partial disassociation of OH = low conc of OH+ions
• -strong  alkali=total disassociation of OH = high conc of OH+ions

• -crush and grind using mortar and pestle
• -add water and stir or heat to dissolve
• -filter to remove excess undisolved

• -Add pure Cu at cathode 
• -Add impure Cu at anode
• -Add CuSO4 as electrolyte
• -it will break into Cu+ and SO4- 
• -Cu+ will go to cathode and gain electrons becomin Cu and forming metal layer
• -SO4 - will go to anode react with Cu and form CuSO4 
• - which will break into Cu+  and SO4- and repeat 
• - cathode will get thicker 
• -anode gets thinner 
• -immpurities will fall down

when extracting Al from its ore we dissolve Al2O3 in molten crayolite

• -decrease melting point of Al203
• -dissolves Al2O3

• -dissolve MgO in water 
• -litmus paper turns Blue

condensed water droplets

• -Cu -Au -Ag -Pt
• they are less reactive than hydrogen

• BY TITRATION
• -measure known amount of HCL and add to beaker 
• -add universal indicator and it turns red 
• -add drop by drop of Na(OH)2 using the burette while swirling to mix
• -stop when indicator turns green and mark end point
• -repeat without using indicator 
• -evaporate water leaving NaCl crystals behind 
• -rinse and leave it to dry

• -measure known amount of HCL
• -add CuO till excess no more reaction is taking place 
• -filter off excess unreacted CuO 
• -evaporate water leaving NaCl crystals behind 
• -rinse and leave it to dry

• -get flask and add HCl
• -add CuO till excess
• -filter off by filtration
• -solution becomes acidic turning universal indicator green and ph 7