mock rev - need to memorize Flashcards
equation linking moles, mass and Mr
moles = mass / Mr
general formula for alkanes
CnH2n+2
general formula for alkenes
CnH2n
colour and state of chlorine at room temp
yellow/green gas
colour and state of bromine at room temp
red/brown liquid
colour and state of iodine at room temp
grey solid
colour of bromine solution
orange
colour of iodine solution
brown
test for alkenes vs alkanes
bromine water reacts with alkenes, go from orange to colourless
equation linking moles, concentration and volume
moles = conc x volume (dm3)
conversion between cm3 and dm3
1dm3 = 1000cm3
how to calculate moles of gas if volume is known
moles = vol (dm3) / 24
define ionic bond
the electrostatic attraction between oppositely charged ions
define covalent bond
the electrostatic attraction between two nuclei and shared pair of electrons
define metallic bond
The electrostatic attraction between positive ions and a sea of delocalised electrons
what types of elements are ionically bonded
metals + non-metals
what types of elements are covalently bonded
non-metal + non-metal
what types of elements are metalically bonded
metals
how to do water of crystallisation questions
Step 1: Work out the mol of unhydrated salt
Step 2: Work out the mol of water (can figure out mass by mass lost)
Step 3: Find the mol ratio of unhydrated salt:water (tips: Divide the both number with smaller number)
define homologous series
a family of molecules with similar chemical properties, the same general formula and the same functional group
define hydrocarbon
an organic compound that contains carbon and hydrogen only
define functional group
the group of atoms that control a compound’s chemical properties
what are the reactants and products of catalytic cracking
long chain alkane –> alkene + shorter chain alkane
catalysts used in cracking
silica or alumina
temp range needed for cracking
600-700 C
when would u use ‘electrostatic forces of attraction’
applies to all types of bonds, because they’re all EFOA between something positive and negative
when would u use ‘intermolecular forces of attraction’
only for simple covalent structures, they’re the only ones with bonds within
when would u use ‘forces of attraction’
only when talking abt graphite: layers slide over each other due to weak forces of attraction
test for ammonia
turns damp red litmus paper blue
test for chlorine
bleaches damp blue litmus paper
test for water
turns anhydrous copper sulphate from white to blue
colour of lithium flame test
crimson red
colour of sodium flame test
yellow
colour of calcium flame test
orange
colour of potassium flame test
lilac
colour of copper flame test
blue/green
what are alkanes used for
petrol
what are alkenes used for
plastics
test for Cu2+ cation
Add sodium hydroxide solution - blue
test for Fe2+ cation
Add sodium hydroxide solution - green
test for Fe3+ cation
Add sodium hydroxide solution - brown
test for chloride anion
Add acidified silver nitrate solution - white precipitate
test for bromide anion
Add acidified silver nitrate solution - cream precipitate
test for iodide anion
Add acidified silver nitrate solution - yellow precipitate
