Mixture, separation Flashcards
What are the states of matter
Liquid
Solid
Gas
What are examples of the three states of matter
Water
Ice
Steam
A description of a liquid in terms of particles
Closer than gas but further apart than solid no order
A description of a gas in terms of particles
They move in random directions
A description of a solid in terms of particles
In an organised form
What is the freezing point of stearic acid
69
Why on a graph when something is changing state does the line level out
Because it needs time to break or make the bonds
What is the process in which a liquid turns to a solid
Freezing
What is the process in which a solid turns into a liquid
Melting
When a solid turns to a liquid what happens to the energy and bonds
Energy is gained and bonds between the particles weaken
When a liquid turns to a solid what happens to the energy and bonds
Energy is released and stronger bonds form between particles
Why would naphthalene have a higher melting point than stearic acid
Stearic acid has less energy
What does the amount of energy needed to change state from solid to liquid and from liquid to gas depend on
The strength of the forces between the particles of the substances
What is a pure substance
A single element or compound not mixed with any other substance
What can a pure substance mean in every day language
A substance that has nothing added to it so it is unadulterated and in its natural state e.g. milk
What is an element
A substance made up of only one type of atom
What is a molecule
When the atoms are joined in groups of two or more
What is a compound
They contain two or more different types of atoms chemically bonded
How is a compound made
When atoms of different elements react and join together
What are the properties of mixtures
Elements can be in any proportions
Each element still has its own properties
Can be separated by physical means e.g. temperature
Small energy change involved
What are the properties of a compound
The proportions of elements never vary
Very different properties to the elements it’s made up of
Separated by chemical reactions
Large energy changes involved
What is a mixture
Contains different particles
Does a pure substance melts and boil at specific temperature
Yes
Does a mixture melt and boil at specific temperature is it
No over a range
What is a formulation
A mixture that has been designed as a useful product
What are some examples of formulations
Alloys Fertilisers Fuels Medicines Cleaning agents Food and drinks Paint
I how would you separate solids of different sizes
Sieving
How would you separate an insoluble solid from a liquid
Filtering
How would you separate a solvent from a solution
Distillation
How would you separate a soluble solid from a liquid
Evaporation
How would you separate a mixture of dies
Chromatography
What does insoluble mean
A solid that will not dissolve in a solvent
What does soluble mean
A solid that will dissolve in a solvent
What is a solvent
A liquid in which chemicals dissolve to make a solution
What is solute
A substance that is dissolved in a solvent
What is fractional distillation
When a substance is separated according to the different boiling points when the solution is heated Ethan will evaporate first and be collected the water will remain behind until its boiling .100° is reached
What is simple distillation
It is used to obtain a solvent from a solute the solution is heated so that the solvent evaporates the solute is left behind the gas cools in the condenser and turns back into a liquid this liquid is collected and is pure solvent
In chromatography what are the substances separated according to
How strongly they stick to the paper
How soluble they are in the solvent
How does chromatography work
The water is drawn up by capillary action when is the solvent reaches the ink spots they are dissolved and carried with the water as it moves up the people the most soluble in travels the fastest what’s the less water soluble inks are left near the bottom of the paper
What is capillary action
Sticky attractive force between water molecules and the paper
What does RF stand for
Retention factor
What is the RF
The ratio of the distance travelled by the sample to the distance travelled by the Solent
What is the formula for RF
RF = distance moved by sample
Distance moved by solvent
What is a solution
A solute dissolved in a solvent
What is a non-aqueous solution
A solution where the solute is dissolved in a solvent isn’t water
What is an aqueous solution
A solution where a solute is dissolved in water
