Slides in this set
·Atoms of the same element
· Same number of protons and electrons
·Different number of neutrons
Atomic number is the number of protons in the nucleus of an atom.
Mass (nucleon) number is the number of protons and neutrons in the nucleus.
An ion; is a positively or negatively charged atom or a covalently bonded
group of ions, a molecular ion
Particle Relative Relative
mass Charge If an ion is positive then it has lost
electrons if an ion is negative then it
Proton 1.0 1+
has gained electrons!
Neutron 1.0 0
Electron 0.0005 1-…read more
Relative Isotopic Mass is the mass of an atom
of an isotope compared with one twelfth of
the mass of an atom of Carbon-12
Relative Atomic Mass is the weighted mean
mass of an atom of an element compared with
one twelfth of the mass of an atom of carbon-
Amount of Substance and Mole
Amount of substance is the quantity measured in mols. Chemists use "amount of
substance" as a means of counting atoms.
The Avogadro constant is the number of atoms per mole of carbon-12 isotope.
A mole; is the amount of any substance containing as many particles as there are in
exactly 12 g of the carbon 12 isotope
Molar Mass, M, is the mass per mol of a substance. The units are g mol -1…read more
Empirical Formula and Molar Volume
The empirical formula is the simplest whole number ratio of atoms of
each element present in a compound.
The molecular Formula is the actual number of atoms of each element in a
The volume per mole of gas. It can be
calculated using the formulas on the left.
Concentration of a solution means the
amount of solute, in mol, dissolved per
decimetre cubed.…read more
HSO Sulphuric acid
HCL Hydrochloric acid
HNO Nitric Acid
HCOOH Methanoic Acid
Citric acid C H O
When an acid is added to water the acid releases H+ ions (protons) into the
solution. The H+ ion in acids is responsible for all acid reactions
An Acid is a species that is a
proton donor.…read more
Metal Oxides MgO (used to cure indigestion), CuO
Metal Hydroxides NaOH, Mg(OH)
Ammonia NH, Amines CHNH
Calcium Hydroxide Ca(OH) Lime for treating acid soils
A Base is a species that is a proton acceptor
Bases neutralize acids.
An Alkali is a type of base that dissolves in water forming OH- ions
A base readily accepts H+ ions to form an acid
Sodium Hydroxide NaOH
Potassium Hydroxide KOH
Ammonia NH…read more