Qualification > Sciences
CHEMISTRY.. SEPERATING TECHINQUES quiz on TUESDAY.. help
Amii:
--- Quote from: ~Vin~ on September 29, 2010, 09:01:51 pm ---hahaha but still, they're too many. ;)
yeah you too. :)
Oh, best of luck. You'll do really well. ;)
Extraction of Iron
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thank u :D :D
The Golden Girl =D:
Esha u deserve a + 1000000000000000000000000000000000000000000000000000000 infinity rep <3
Honey it is AMAZING <3
The Golden Girl =D:
--- Quote from: wanabeastarstudent on September 29, 2010, 07:02:50 pm ---:O so chromotography is involved??
--- End quote ---
habeebti don't ya remember when mr.sumaiah used to give u Qs in her exams and if u look in her notes it's within the first two chapters i guess ;)
Vin:
--- Quote from: wanabeastarstudent on September 29, 2010, 11:55:38 am ---*state of matter
*seperating techniques and mixtures
--- End quote ---
The three states of matter :
>Solid
>Liquid
>Gas
Properties of solid
Rigid – fixed definite shape
Highly incompressible
Least intermolecular space
Intermolecular force of attraction is greatest
Type of motion of molecules : They vibrate along their mean position
Properties of liquid
Indefinite shape – takes the shape of the container
Incompressible
Intermolecular space greater than solids and lesser than liquids
Intermolecular force of attraction lesser than solids
Type of motion of molecules : Random, constant movement of molecules
Properties of gas
Indefinite shape – Completely fills the container creating a specific amount of pressure of the walls (dependent on the concentration of gas/number of molecules)
Highly compressible
Greatest intermolecular space
Intermolecular force of attraction least.
Type of motion of molecules : Random and uncertain (Brownian motion)
(also refer ppt)
Separation techniques and methods:
>Mixture of two solids : one soluble in water, other insoluble - Dissolve the mixture in water> Filter the contents> Dry the residue on paper> Evaporate the solution to obtain soluble solid.
>Mixture of solid particles (eg. sand) and water : Sedimentation (allow the solid to settle) > Decantation (carefully pour the solution from the container in order to leave the (sand) particles in the bottom of the original container. > Filtration (Filter any solid particles present after decantation in the solution of water)
>Mixture of solid particles (eg. sand/salts etc) and iron > Use magnet.
>Mixture of two or more miscible liquids > Fractional distillation
>Mixture of two miscible liquids > Separating funnel.
>Idea of chromatography
[refer ppt for more info and diagrams]
Vin:
--- Quote from: wanabeastarstudent on September 29, 2010, 11:55:38 am ---
*atomic structure
*bonding (metallic,covalent,ironic and macromolecular)
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Atomic structure.
An atom consists of a nucleus and particles revolving around it at high speeds called electrons. These electrons are placed in different energy levels. If these electrons stop revolving, or slow down their motion, the nucleus will attract them towards itself (due to the difference of charges) and 'consume' them.
The nucleus consists of neutrons and protons. The nucleus determines the mass of the atom and the proton number determines the Atomic number of the atom.
The distribution of electrons for normal elements is as follows, i.e the maximum number of electrons each shell can accommodate:
1st- shell: K -> 2
2nd- shell: L-> 8
3rd- shell: M-> 18
4th shell: N -> 32
and so on.. The general formula is 2n2. Where 'n' is the shell number.
Remember:
(In reference to the Periodic table)
All the elements in the same group (column) have same number of outer shell electrons (also known as valence shell electrons)
The period number shows how many shells there are for each element.
Proton - Positively charged particles. Found in the nucleus. Atomic mass of 1.
Neutrons - No charge. Also present in the nucleus. Atomic mass of 1
Electrons - Negatively charged particles. Orbit around the nucleus in specific paths. Mass negligible (1/1837)
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