Paper 1 Key Things Flashcards
What is a solvent
The liquid which dissolves a substance
What is a solute
The substance dissolved in the solvent
What is a solution
A liquid mixture of the solute and solvent
What substance would you use to show diffusion in liquid
Potassium Manganate (VII)
Which gases are released from which substances in the ring diffusion test
Aqueous ammonia releases ammonia gas
Hydrochloric acid releases hydrogen chloride gas
Where does the ring form in the tube for the ammonia hydrochloric acid test and why
Nearest to the hydrochloric acid because ammonia particles diffuse faster as they are lighter and smaller
What is an atom
The smallest particle of an element
What is a molecule
A cluster of two or more NON METAL atoms joined by COVALENT bonds
What is an element
A pure chemical substance which cannot be broken down into a simpler substance and is listed on periodic table
What is a mixture
An impure substance that is made from more than one element or compound which are not chemically bonded together
What is a compound
A pure substance made from more than one element chemically bonded together in a fixed ratio
How do you test to see if a substance is pure
You boil it and see if it boils at the correct temperature given from a data book
What method would you use to separate out a linguist from a solution
Simple distillation
Describe the process of distillation
Solution is heated
The part of solution with lowest boiling point evaporates
The vapour is cooled and condenses back into liquid
This is collected
This collected liquid is now pure
Suggest a problem with simple distillation
Only can separate things with very different boiling points and only can separate one thing from a solution
What must be included in a diagram of simple distillation
Flask containing solution Still head (where gas evaporates to) Thermometer Water in (from bottom) and water out (from top) of condenser Container to collect distillate
What is fractional distillation used for
Separating a mixture of several liquids
What is a fraction
A liquid that has been separated from a mixture using fractional distillation
Describe the process of fractional distillation
Heat mixture
The liquid with the lowest boiling point will evaporate first and reach the top (cool) part of the fractionating column
Other liquids may also evaporate but will condense before reaching the top
The liquid goes into condenser and condenses to liquid
Temperature is raised so the next liquid will evaporate to the top and process repeats
What is filtration used for
To separate an insoluble solid from a liquid
Describe the process of filtration
Filter paper folded into cone shape and placed into funnel
Funnel placed in a flask
Pour solution into filter paper
Insoluble solid left behind as residue
What method would you use to separate a solid solute from a liquid
Crystallisation
Describe the process of crystallisation
Solution placed over beaker of water
Beaker of water heated with bunsen burner
Steam heats solution
Continue heating until half of the solution has evaporated
Leave the evaporating basin containing the solution to dry in a warm place for a few days
Remove crystals with tweezers
What method would you use to separate a mixture of soluble substances
Paper chromatography
Describe method of chromatography
Draw a pencil line near the bottom of a sheet of filter paper
Add spots of different inks or solutions along the line
Place the bottom of the paper into a solvent (usually water)
As the solvent moves up the paper, substances which are more attracted to the water move up faster and further with it and substances which are less attracted move slowly and less up the paper
Allow paper to dry
The result is a chromatogram
What is the mobile phase in chromatography
The solvent which moves up paper (water)
What is the stationary phase in chromatography
The substance that stays still (paper)
What is used in chromatography to show colourless results
Locating agent
What is the rf value in chromatography
The ratio between the distance travelled by solute and solvent
How to calculate rf value
Distance travelled by solute / distance travelled by solvent
What is the relative mass of an electron
0.0005
What is the atomic number and where is it
Atomic number is on bottom and tells you how many protons there are (and therefore also how many electrons)
What is the mass number and where is it
Total number of protons and neutrons and is on the top
What is relative atomic mass
The mass of an atom compared to that of a carbon-12 atom
What is an isotope
Different atomic forms of the same element which have the same number of protons but different number of neutrons
Same atomic number different mass number
What is the difference in properties of an isotope
Isotopes have identical chemical properties as electrons are the same
Different physical properties eg density changes
What is the relationship between elements in the same group (2 things)
Similar chemical properties
Same amount of electrons on outer shell (which is the group number)
What does the period number show
The number of shells of electrons
How does acid-base character of oxides determine if it is metal or non metal
Metal oxides are basic
Non metal oxides are acidic
Why are the noble gases so unreactive
Because they have a full outer shell of electrons
Equation for mass mol mr
Mass= Mr x mol
What is the mole number
6x10 ^ 23
Formula for percentage yield
Actual yield / theoretical x100
What you actually got / what you should have gotten x100
How to find molecular formula
Find mass of empirical formula (basically find the mr)
Divide the given molecular mass by the mr of the empirical formula
Multiply each number of the empirical formula by that number obtained from previous division
Define empirical formula
Simplest whole number ratio of the different elements in a compound
Define molecular formula
The actual number of atoms of each element in a given molecule
Charges of ions which must be learned
Ag+ Cu2+ Fe2+ Fe3+ Pb2+ Zn2+
H+ OH- NH4+ Co32- No3- SO42-
Why do giant ionic lattices have high boiling points
Strong electrostatic attraction
Requires lots of energy to break
Which is supplied through heating
What must be done to ionic compounds to make them conductive
Melt them or dissolve them in water to make the ions mobile
Definition of ionic bond
A bond formed between a metal and a non metal which involves a transfer of electrons
Definition of covalent bond
Bonding between two non metal atoms involving shared pairs of electrons
Which is the only giant covalent substance that conducts electricity which is also the only non metal that conducts
Graphite
Why does the boiling point increase with mr for simple molecular substances
There are more points along a larger molecule for intermolecular forces to form so there are more forces of attraction
Why is diamond hard
Does it conduct electricity
Rigid lattice structure held together by covalent bonds
Doesn’t conduct as it has no delocalised electrons
Describe and explain properties of graphite
Lubricant - slippery because layers can slide over each other as the layers are held together by intermolecular forces (remember that the layers are covalent bonds)
High melting point- covalent bonds
Conducts electricity- each carbon atom uses only 3/4 electrons on the outer shell so there is one free one which is delocalised
Why is C60 fullerene soft
Because it has weak intermolecular forces between the molecules so the layers can slide over each other
Can C60 fullerene conduct
Yes because it has a delocalised electron, however it conducts poorly because the electron cannot move between molecules
