Chemisty Flashcards
How particles arranged
Solid - ordered
Liquid and gas - random
How particles move
Solid
Liquid
Gas
Solid - vibrate only
Liquid - move freely
Gas - move fairly freely
Why do liquids and gases take the shape of their container
Particles can move around
Why do solids not take the shape of their container
Particles cannot move around
Why can gases be squashed easily
There are big spaces between the particles which can be pushed closer together
Why can’t solids and liquids be squashed easily
Particles are close so cannot be pushed closer together
Liquid to solid
Freezing
Solid to liquid
Melting
Liquid to gas
Evaporation
Gas to liquid
Condensation
Solid to gas
Sublimation
Gas to solid
Deposition
In an atom where are all the
Protons
Neutrons
Electrons
Nucleus
Protons, nucleus - in the center
Electrons - on the outer lines
Relative mass/charge of
Proton
Electron
Neutron
Relative mass
Proton, neutron - 1
Electron - 0
Charge
Proton +
Neutron I
Electron -
Why are atoms always neutral
The number of electrons in an atom is always equal to the number of protons
So an atom as a whole is electrically neutral
Mon-
Di/bi-
Tri-
Mono - 1
Bi - 2
Tri - 3
SO3
NO
NO2
SO3 - sulphur trioxide
NO - Nitrogen monoxide
NO2 - Nitrogen Dioxide
What elements would you react together to make iron oxide
Iron and oxygen
Atoms in
CO2
CuSO4
CO2 - 1 carbon 2 oxygen
CuSO4 - 1 copper 1 sulphur 4 oxygen
Stoichiometry
Chemical quantites in chemistry
where ratio of amounts of each substance in a chemical reaction is balanced
What do word equationss represent
Changes that happen in chemical reactions using names of substances involved
What do Balanced chemical equations represent
Represent changes that happen in chemical reactions
using formulae of the reactants and products
Molar mass
Mass of 1 mole that substance equal to
Relative atomic mass
Relative formula mass
Molar mass
SO2
(SO4)3
SO2 | 16 + (2x8) = 32
(SO4)3 | S3 + O7
Mole
the unit for amount of substance
How to work out | Number of moles of atoms
Mass in grams
____________________
Molar mass of atoms
Mass (g)
Molar mass (g/mole) x amount (mol)
Avogadro’s constant
Number of atoms, molecules or ions in a mole of any substance
23
6.02 x 10 Per mole
Reactants
Starting chemicals in a chemical reaction
Relative formula mass
F2
H2SO4
F2 - 2(19) = 38
H2SO4 - 2(1) + 32 + 4(16)
Number of moles in each substance
90.0g of H2O
685g of NH3
90 ➗ 18 = 5 moles
685 ➗ NH3 (10) = 68.5
Mass of substances
4.00 moles of N2
0.100 moles of HNO3
4.00 x 28 = 112
0.100 x 63 = 6.30g
0.0200 moles of a compound is found to have a mass of 1.64 g
Find the formula mass of the compound
1.64 ➗ 0.0200
Pure substance
Contains only 1 substance
In a graph
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📈📉
Where is the melting point of the substance
The first _____________
What do nucleus of an atom contain
Protons amd neutrons
How many electrons
24
Mg
12
12
How many moles of helim atoms in
24
2.4 x 10
4.0
Names
CO
Carbon monoxide
Element
Pure substance
made of one type of atom
Compound
Two or more different elements chemically bonded/joined
Mixture
consists of two or more different substances, not chemically joined together
Wat does property of substance do
Describe what it looks like and how it behaves
What are the states of matter
Solid liquid gas
Which states of matter can compress
Which states of matter can flow
Compress
Solid liquid - no
Gas - yes
Flow
Solid - no
Liquid gas - yes
Shape
Solid
Liquid
Has
Solid - fixed unless you apply a force
Liquid - takes shape of the bottom of its container
Gas - takes shape of whole container
How draw liquid
Circles that are all touching but move
Boiling point
The temperature a substance boils
How to measure boiling point
Pour liquid into a beaker
Heat liquid and measure temp every min
Plot results on a graph
When can evaporation occur
Happens at any temperature
Force between particles
Solid - strong
Liquid - weaker
Gas - almost none
Energy levels
Solid - little
Liquid - some
Gas - lots
What do horizontal sections on graph show
Energy transferred by heating and not used to change temperature
What happens to the particles when ice cube melts and freezes again
Particles in ice gain heat energy and vibrate more
a solid changes state and becomes liquid
Particles in a liquid lose heat energy and move less quickly
Then a liquid changes state and becomes ice
Dioxide
2
Avogadro’s number - how many particles
1 mole
2 mole
0.5 moles
10 mole
48g
1 mole - 6.02 x 10(23)
2 moles - 6.02 x 2 = 1.20 x 10(24)
0.5 moles - 6.02 ➗ 2 = 3.01 x 10(23)
10 moles - 6.02 x 10(23) = 6.02 x 10(24)
48g Magnesium - 1.20 x 10(24)
% by mass of O in H2O
16
100 x ___ = 88.9%
18
16 = O
18 = H2O
% mass of O in Ca(NO3)2
2(14)
100 x ______ = 17.1%
164
Examples of element
N
Ag
Cl
O
Examples of compound
CuSO4
Pure water (H2O)
Table salt
Carbon dioxide
Examples of mixture
Soil
Seawater
Air
5 properties of solid
Hard/strong
Fixed shape
Cannot be compressed (easily)
Fixed volume
High density
5 properties of a liquid
Can flow
Shape changes to fill bottom of container
Cannot be compressed (easily)
Fixed volume
High density
5 properties of gas
Can flow
Shape changes to fill a closed container
Can be compressed
Variable volume
Low density
Examples of gas
Air
Smoke
Steam
