Ionic bonding

atoms of the same element with different number of neutrons

average of all naturally existing isotopes of an element

electrons: 0

protons: 1

neutrons: 1

number of protons and electrons

Average atomic mass (rounded) - atomic number (# of protons)

smallest individual particle of one type of element

neutral

protons, electrons

ion

an atom or molecule with a net electric charge due to the loss or gain of one or more electrons

same number of protons

becomes an cation because it is now positively charged

becomes an anion because it is now negatively charged

• made of 2 or more atoms that are chemically bound (can be same or different elements)

• O2, N2, H20 (can be other examples)

• made of 2 or more atoms of different elements that are connected by chemical bonds

• all compounds are molecules (but not all molecules are compounds)

• CO2, NaCl, MgO (can be other examples)

two or more ions that form ionic bonds which hold the ions together by the electrostatic forces of attraction

• Ionic bonds form between metals and nonmetals when one atom transfers one or more electrons to another atom.

• This transfer of electrons creates ions with opposite charges, one positively charged (cation) and one negatively charged (anion).

• The electrostatic attraction between these oppositely charged ions forms the ionic bond.

doners

because metals have lesser than 4 electrons in their valence shells so it is easier for them to donate/lose electrons to form a full valence shell

acceptors

because nonmetals have 4 or more electrons in their valence shells so it is easier for them to gain electrons to form a full octet/valence shell

the periodic trend in reactivity of metals increases as you move to the left of the periodic table and down a group

• Metals with more energy levels have valence electrons that are further away from the nucleus, with weaker attraction.

• They lose electrons more easily so they are more reactive as you go down the group.

• Metals further to the right in the same period have more protons so there is a stronger attraction for valence electrons.

• They lose electrons LESS easily and are LESS reactive.

reactivity increases as you move to the right of the period and up a group

• Non-metals with fewer energy levels have a shorter distance between the nucleus and the valence electrons, with stronger attractive force pulling the electrons

  → They gain electrons more readily and are more reactive as you go up the group

• Non-metals further to the LEFT in the same

  period have fewer protons so there is a weaker attraction for valence electrons

  → They gain electrons LESS easily and are LESS reactive.

Group 1

Group 2

Group 17

Group 18

Because it has a full valence shell already.

Because it only has to lose one electron to have a complete valence shell

because it only has to gain one electron in order to have a full octet

boron, silicon, germanium, arsenic, antimony, tellurium, polonium

or

B, Si, Ge, As, Sb, Te, Po

• john dalton 1803

• advantages: recognised that atoms of a particular element differ from other elements

• disadvantages: atoms are not indivisible, it can be separated

• j.j thompson 1904

• advantage: recognised electrons as components of atoms

• disadvantage: this model does not show the nucleus

• ernest rutherford 1911

• advantage: realised positive charge was localised in the nucleus of an atom

• disadvantage: did not explain why electrons remain in orbit around the nucleus

• niels bohr 1913

• advantage: proposed stable electron orbits, explained emission spectra for some elements

• disadvantage: moving electrons should emit energy and collapse into the nucleus, model did not work well for heavier atom'

• erwin schrodinger 1926

• advantage: shows electrons don't move around the nucleus in orbits but in clouds where the position is uncertain, still widely accepted as the most accepted model of the atom

plum pudding model

quantum model

nuclear model

planetary model

solid sphere model

• shiny

• good conductors of heat and electricity

• malleable (able to be hammered or pressed into shape without breaking or cracking)

• poor conductors of heat and electricity

• not malleable

• not ductile (not able to be drawn out into a thin wire)

exothermic

endothermic

• Electrical conductivity refers to a
  substance’s ability to conduct electrons, or
  its ability to allow electrons to move
  through it

• Substances with high electrical
  conductivity will allow electrons to move
  through them with the least amount of
  resistance

A homogenous mixture of solute and
solvent

The substance that can be dissolved within
another substance

The substance that can dissolve another
substance, present in larger amount
(commonly a liquid)

Electrolytes are salts that dissolves in water and
produces ionized (charged) particles that are able
to conduct electricity.