1.1 - Nature Of Substances Flashcards
(37 cards)
Element
One type of atom, cannot be broken down, Building block of all substances
Compound
Two or more types of atom, Chemically joined
Molecules of elements
Two or more of the same atom, Joined by a covalent bond
Molecules of compounds
Two or more of different atoms, joined with a covalent bond
Mixture
Made from different elements of compounds, Not chemically joined
Ar
Relative atomic mass
Where is the Ar found ?
The top number on the periodic table
Mr
Relative formula mass
Mr calculation
(Chemical 1 mass x number of atoms) + (Chemical 2 mass x number of atoms) etc
Methods of separating mixtures
Distillation, Evaporation, Chromatography, Filtration
Distillation
Uses boiling water and condensation to separate a liquid from a solution based off different boiling points
What does distillation separate ?
A liquid from a solution
Evaporation
Where a liquid is heated so it evaporates into a gas and leaves behind a solid
What does evaporation separate ?
A dissolved solid from a solution
Filtration
Where a mixture passes through filter paper to allow the liquid to pass through but not the solid
What does filtration separate ?
An insoluble solid from a liquid
Chromatography
Soluble substances placed on paper in water to show solubility
What does chromatography separate ?
Soluble substances
Ion
An electrically charged particle
How is an ion formed ?
When an atom looses or gains an electron
Positive ion
When an atom looses an ion
Negative ion
When an atom gains an electron
Chemical change
When a reaction happens, atoms not created or destroyed, atoms rearranged to form new chemicals
Physical change
When a substance changes without becoming a new chemical, for example freezing
