Science Autumn

Hypothosis: observation backed with creative thinking and scientific knowledge.

Trial run: tell you how early thoughts will work out.

Range: max or min values of indepndent or dependent variable.

Accurate: mesurements are close to true values.

Precise: mesurements which theres very little spread about the mean.

Random error: results will differ.

Catorgoric error: method crried out costantly but error still occured.

Anomiles: 1 result is out of line.

Anomolous: more han one result is out of line.

Independent varible: the thing that changes.

Dependent varible: thing that stays the same.

Valid:mesures whats ment to be mesured with an appropriate level of performance.

Reproducable: experiment repeated by another person using different method or equipment.

Repeatable: origanal experimenter repeats same experimentusing same method and equipment.

Mean: add all numbers together and devide by how many numbers there are.

Range: subtract lowest result from highest to find range.

Median: arrange numbers in assending order and find middle number.

Rules for drawing tables:

should be drawn in pencil.

independent varible in left colum.

only write whole numbers.

units go in headings of table.

Rules for drawing graphs:

draw in pencil

independent varible on x axis.

dependent varible on y axis.

Properties and uses of aluminium:

silver,shiney metal

aloy which is a mix of elements.

light and has low density.

good conducttor of electricity.

reactivemetal and dose notcorrode easily.

used for cans, foil, saucepans, bikes, aeroplains+ space viecles, high voltage electricity cables.

has oxide  layer on outer layer.

Extracting aluminium:

they use electrolsis, which passes electric currents through molten aluminium oxide to break down.

cant be extracted by carbon because aluminium is higher on reactive series.

aluminium oxide is found as an ore.

electrolsis is an exspensive method and causes enviromental issuses because it uses a lot of energy.

Properties and uses:

silvery, white metal

very strong and resistant to corrosion.

has oxide layer on surface

its dense but not as dense as most metals

very high melting point at 1160 c

used for high performance racing bikes + aircraft, part of jet engines, part of neuclear reactor and hip joint replacements.

Extracting titanium:

uses carbon to extract from oxide form.

carbon reacts with it making it brittle.

titanium ore must be processed which involves seperating the oxide from titanium.

uses more reactive metalsto displace it like sodium or magnesium.

particals are made up of 3 things which are called electrons, shell and neucleus. on the shell there are electrons. the  necleus contains prfotons and neutrons.

reletive charges:

protons have positive charge

neutrons have no  charge

the necleuas overall has a positive charge.

eletrons have negative charge.

the first shell can only hold 2 electrons.

the rest after can hold 8 and then a new shell starts.