Elements and Compounds - Chem (ch.03) Flashcards
Matter
anything that has mass and occupies space
Atom
smallest unit of matter than can be divided
Element
a pure substance made up of only one kind of atom and it cannot be broken down by chemical means
Molecule
group of 2 or more atoms that are chemically bonded together
Orbits
the fixed paths that the electrons of a nucleus move around
example of liquid non-metal
bromine
total no. of elements
118 (94 are natural)
Examples of metals
gold, iron, silver, copper, zinc etc
Metalloids
elements that exhibit intermediate properties between those of metals and non-metals
Noble/Inert Gases
elements that are highly stable and do not react chemically with other elements
Compounds
pure substances made up of atoms of two or more different elements chemically combined in fixed ratios
chemical formula
expression which states the number and type of atoms present in 1 molecule of a compound
chemical formula of sulphate of soda
(sodium sulphate) Na2SO4
chemical formula of vinegar
CH3COOH
chemical formula of rust
Fe2O3 x H2O
chemical formula of plaster of paris
CaSO4 . 1/2H2O
Mixture
physical combination of two or more pure substances
types of mixtures
homogeneous and heterogeneous
Alloy
homogeneous combination of one metal with 1 or more metal(s) or non-metal(s)
Substance present in larger amount in solutions
Solvent
substance present in smaller amount in solution
Solute
Emulsion
a mixture of two or more normally immiscible liquids
Suspension
type of heterogeneous mixture in which small particles are suspended in a liquid
Need for separation of substances
to remove harmful or undesirable impurities
to obtain a useful substance
to obtain the pure sample of a substance
Sublimation
some substances, when heated, pass directly into the gaseous state from the solid state without entering the liquid state
(this is called sublimation)
Reverse process of sublimation
Reverse sublimation
deposition
(either)
Example of sublime solids
camphor, iodine, napthalene
Evaporation
the process of evaporation involves heating the solution until the solvent evaporates
Distillation
this process involves separation of a liquid from a solid- liquid mixture in which solid is soluble in liquid
pure liquid obtained after distillation
distillate
solid left in the flask after distillation
residue
misicibility
ability of a liquid to dissolve in another liquid
method of separating miscible liquids
simple distillation
method of separating immiscible liquids
seperating funnel
first person to use chromatography
Mikhail Tsvet
red pigment found in leaves
anthocyanin
blue-green pigment found in leaves
chlorophyll a
yellow pigment found in leaves
xanthophyll
orange pigment found in leaves
carotene
yellow-green pigment found in leaves
chlorophyll b
used of chromatography
forensic testing
Dope testing of athletes
Food Testing
Medicine
how many neutrons does deuterium have?
1
how many neutrons does protium have?
0
how many neutrons does tritium have?
2
What is RF?
Retention factor
How do you calculate RF value?
RF = distance travelled by the component from the original line/distance travelled by the solvent from the original line(solvent front)
