C1 Flashcards
What is a particle?
Atom
A tiny bit of matter
Smallest particle of an element that still has its chemical properties
Particle model for each
What does particle model show
Lomtieruojs
Solid
- regular arrangement
- very Close distance between particles
- vibrate fixed positions (fixed so dan’t flow over ach other)
Liquid
- random arrangement
- still relatively close distance between particles (therefore can’t compress
- move around each other (flow) ( this means they can occupy any volume they go into)
Gas
- random arrangement
- particles far away from each them (can compress)
- particles move qucky in random directions
1) doesn’t show the space between,
2) actual size of lsrtickes
2) forced
4) psrtciels aren’t just spheres
What is a formulation
Physical chemical
A mixture that has been designed to be useful eg fertilster, washing product but not water.
Chemical change is nit easily revesible , diffuclyt , sunayxne msde, propertied diffeeende, neutralisation
Apparently for covalent?
How do atoms react
Atoms react to gain the same electron configuration as the nearest noble gas
Why are metals good conductors in heat?
Metals are good conductors of heat because the delocalised electrons allow thermal energy to be transferred easily through the substance.
5
What is characteristic of low density poly ether (lode)
Polymers are branched, meaning they are arranged randomly therefore allowing them to be weak and flexible.
This makes them ideal for bags and bubble wrap
L
During which change do particles lose energy to the surroundings?
H
Why do some people have concerns about the use of nanoparticles in sunscreens?
There is some concern that nanoparticles used in sunscreen and other cosmetics could enter the bloodstream with unpredictable results. More research and longer-term studies are needed.
When do we use “di” as prefix
The name of the chemical compound MgF2 is magnesium fluoride. We only use “di” in covalently bonded compounds.
Strong acids
Fully dissociates into ions when dissolved in water and the change is not reversible
Electrolysis of aqueous salts
The thing that is least reactive is produced at cathode and reactivity series, and more reactive in na7oncs…
In reactivity series, copper last c
Calling = calcium first c (ca for both)
CARELESS NOW= Carbon (car)
Platinum at end
Please stop calling me a careless zebra I think love has come so god please
LEARN ELECTROPLATING
E
Which halogen is a liquid at room temperature?
Brominw
What ,ade Statue of Liberty like it is
CuO?
What are limitations if the particle model?
The particle model does not take into account
- the size of each particle
- the forces between them
- the space between particles x too big to show
Doesn’t show forces in gas, distance, size are all the same…
Atom molecule element
Bond length
Atom smallest particle of an ale meant
Element made out if one atom
Molecule made out of two or more
Bind length is 2 radii
Briefly summaries Dalton and Mandem
1) first dalton. Who suggested wllmmstternis made from stokes, and that atoms of an element are the same, different elements different atoms. Saw them is small indestructible balls.
2) Next Thompson , who worked out cathode rays were negatively charged through magnetic fields and did experiments with the,. From this he saw the cathode rays must be coming fork inside the atom, therefore the atom was described to have negative electrons dotted around the atom, and a ball of psoorve mass to Dougherty the charge
- he said charge if atom is and TEHY CONSTAIN ELECTORNS.Z
2)rutherford, mares en and Geiger,
Tried to prove the plum pudding model. They worked out sohos particles with positively charged using electric fields, and decided to fire them at gold foil .
- expected it to go straight through as change was considered to be evenly spread around the atom. While most did come through, SOME CHANGED DRIECRJON, SND SOME CAME BACK 90.
- this showed that since msotnwent htiugh, it was empty space
But since some came back, there was a positive mass in the middle, nucleus that was reflecting them.
2 said electrons orbit outside like a SOLAR SYSTEM
4) Bohr used mathematical experiments . He knew that according to Rutherford eventuakkybthe electrons would spiral in and collide with the atoms. He improved and said electrons sit in fixed energy levels around the electron at fixed distance .
Remember formula mass / molar difference with atomic?
Atomic for one molecule, formula for all
Molar mass misleading ?
Pure
How to see it pure
Substance containing one element of one compound
Pure substance will have a certain boiling and melting point. If a substance being tested melts over a range of temperatures, or at the wrong temp, then its’ not pure
Alloy?
A metal mixed with one or MORE ELEMENTS, makes it more useful
How to see melting point (practical key bits)
1) MUST STIR THE LIQUID MAINTING A CONSYANT TEMO
2) heat it slowly so it even improve accuracy
When temo stops rising that’s melting point
Sollte solvent solution difference
Solute is alt
Solvent water
Solution both
Filtration
Uses to separate a insoluble solid (sand) from liquid (water)
Use filter paper, as this has holes small enough. Residue (sand) stays, filtrate (water ) goes through. Makes sure to to FLUTE A FILTER PAPER ( HELLA FOLD)
Crystallisation or (distillation)
Separates the solute from solvent, distillation separates the solvent from solute, but both similar,
Chrstallation:
1) pour solution in evaporating dish, gently hets it up, HAS RO BE GENTLE or won’t work. Some of the solvent evaporates making it more concentrated.
2) once it reaches saturation (where adding more salt won’t dissolve because less water now), remove the what and let it fool down. As it cools, solubility will decrease and crystals begin to form
3) bigger crystals mean gentler heat
4) filter the rest out to just get crystals then a DRY
