Separating Mixture and Conservation of Mass Flashcards
What are the four state symbols and what do they stand for?
(s) solid
(l) liquid
(g) gas
(aq) aqueous
What is an element?
A substance made up of only one type of atom
What is a mixture?
A substance that contains several different substances that are not chemically bonded together
What is a compound?
A substance made up of two or more different types of atoms chemically bonded together
In everyday language what is a “pure” substance?
A substance that has had nothing added to it and is in its “natural” state
In chemistry what is a “pure” substance?
A substance made of a single element or compound
How can pure substances be distinguished from impure ones?
By their melting/boiling points
What are the melting and boiling points of pure substances?
One very specific temperature
What are the melting and boiling points of impure substances?
They change state at a range of temperatures
What is a formulation?
A mixture made to a specific recipe and designed for a specific purpose
Give three examples of formulations.
Any three from: paint, detergents, medicines, cosmetics
What type of mixture can be separated by filtration?
A liquid and an insoluble solid
What is crystalliasation?
A process where water is evaporated from a solution to produce solid crystals of the substance dissolved
What is distillation?
A process that separates a liquid from a solution (or mixture of liquids) by evaporating and then condensing the liquid
What is fractional distillation?
A process to separate a mixture of liquids that have similar boiling points
What is chromatography?
A process to separate the constituents of a mixture
How can chromatography show the difference between pure and impure substances?
Pure ones will not separate into a number of spots
In chromatography, why must the substances be placed on a pencil line?
Pencil will not dissolve in the solvent
In chromatography why must the solvent height be lower than the pencil line?
So that the substances do not dissolve into the solvent off the paper
What is the conservation of mass?
That atoms cannot be created or destroyed
When a metal forms a metal oxide, why does the mass increase?
Because oxygen atoms from the air have been added
When an acid reacts with a metal, why does the mass decrease?
Because a gas is produced and escapes
