chemistry revision Flashcards
what is the atomic number
the number of protons
the mass number is?…
the number of protons + neutrons
what is an isotope?
something that has the same number of protons as that defines the element, and different numbers of neutrons.
what is the configuration for 16 electrons in shells
2,8,6
what are the sections on the periodic table
left - metal, right - gas, between - semi-metals
how many types of atom does a compound have?
2 or more
what is CuSO4?
copper sulphate
what is lithiums reaction to oxygen?
goes dull
what is sodiums reaction with oxygen
went dull quickly
what is potassiums reaction with oxygen
went dull fastest
what is lithiums reaction with water?
fizzed, floated, moved and dissolved
what is sodiums reaction with water?
fizzed, floated, moved around, melted into a ball
what is potassiums reaction to water?
exploded, floated, sparked into a lilac flame, moved quickly around/
which group seven metal is the most reactivve with the air?
francium
why are the elements at the bottom of group 7 the most reactive?
the electrons are further from the nucleus, theres a lower attraction.
what are the main three halogens?
chlorine, bromine, iodine
what are chloride and bromide’ reactions to the silver nitrate test?
cloudy white with a white precipitate
what are the flame colours for the following elements in order: lithium, sodium, potassium, calcium, barium
brick red, orange, lilac, orange/yellow, pale green.
as we go down group 1 the density…
increases
what are noble gasses
they are unreactive gasses as they have aa full outer shell.
what are the four factors affecting collision theory?
surface area, concentration, catalysts, temperature
what is the reaction rate equation?
change in amount of substance / time taken
what are the three types of water?
hard water, soft water, temporary hard water.
how do you purify drinking water?
sedimentation, sand filter, chlorination and storage
why is chlorine and flourine added to the water?
to kill bacteria and prevent tooth decay.
does nitrate ions make water undrinkable?
yes
how do you seperate ethanol and water?
boil the solution at 78 degrees so that the ethanol evaporates and is condensed in a condensing tube and then collected in a beaker.
does hard water need more soap to sud?
yes
can temporary hard water be boiled into soft water?
yes
what substance can change any water in to soft water?
adding sodium carbonate as it displaces other molecules.
what was alfred wegners theory?
that all of the continents once fit together
what was wegners evidence for his theory?
the plates fit in a jigsaw pattern, there are the same fossil and rock formations on the other side of oceans and no where else.
what is wegners super continent?
pangea
how does a volcano map relate to tectonic theory.
around where the tectonic plate boundarys are there are earthquakes and volcanoes almost outlining the plates.
how to the tectonic plates move?
by convection currents in the mantle.
what are the two types of crust?
oceanic and continental.
what happens at a constructive plate boundary?
the plates move away from eachother
what happens at destructive plate boundarys?
one plate moves under another.
what happens at conservative plate boundarys?
the plates move alongside eachother.
why does a destructive plate boundary occour?
because one plate is thinner than another so it gets pushed under and melted into magma.
what is the gas test for oxygen?
place a glowing splint into a test tube, if oxygen is present the splint will light on fire.
what is the test for carbon dioxide?
blow into limewater, if the solution goes cloudy carbon dioxide is present.
what is global warming?
the increase of temperature of the surface and atmosphere of the globe.
name 3 greenhouse gasses.
carbon dioxide, methane, water vapour.
name three causes of greenhouse gas emissions.
deforestation, burning fossil fuels, more people.
what are some consiquences of global warming?
ice caps pelting, sea levels rising, freak weather conditions.
define thermal decomposition.
the breaking down of substances using heat.
name the four ‘lime’ stages and how you get there.
limestone, take away co2, quicklime, + small bit of water, slaked lime, + water, limewater, + co2, limestone again.
limestone removes impurities, makes glass, makes concerete and cement and neutrilises soil. true or false.
true
cons of limestone quarrying.
pollution, produces dust, noise pollution.
