period table and bonding

booklet 2

elements in horizontal rows

increasing in atomic mass

vertical columns

same properties

from an elements position on table..:

• work out electron structture

• work out various chemical properties

• how reactive an an element is

all elements:

solids + gasses, except mercury + bromine

group 1

alkali metals ( except hydrogen )

semi metals

B, SI, Ge, As, Sb, Te

group 18

noble gasses

group 2

alkali earth metals

reactive non-metals

hydrogen + groups 14-17
C,N,O,F,P,S,Cl,Se,Br,I

chemical bonding

process where atoms combine to form compounds

why do atoms bond

to become more stable by achieving a full outer energy level

3 types of chemical bonds

1. ionic

2. covalent

3. metallic

ionic bonding

the transfer of electrons which forms an electrostatic force of attraction to an ionic crystal lattice between positive cations and negative anions

positive ions

cations

negative ions

anions

ionic/crystal lattice

3D giant structure formed by arrangement of oppositely charges ions held together by electrostatic forcees

ionic compounds simile

ionic solids / salts

properties of ionic compounds/ionic solids/ salts

• high melting and boiling points

• conduct electricity when dissolved in water or at a molten state

• usually solid and crstayline at room temperature

• brittle

product of ionic bonding

ionic compounds

molten state;

if you could melt salt into a liquid, it would be a conductor of electricity

ions

formed when an atom gains/ loses electrons

covalent bonding

sharing od at least 1 pair of electrons by 2/2+ atoms

covalent bonding occurs between

non metals

covalent bonds found in

small molecules, large molecules and giant covalent structures, such as diamond

properties of covalent compounds

• can be gasses,liquids or solids

• low melting and boiling points

• dont conduct electricity

• often form molecules

diatomic

homoatomic diatomic atoms

diatomi molecules

H, O , F , Br, I , N, Cl
Naturally bond with others ( exist as 2 of same element)

metallic bond

3d attraction between positive metal ions and delocalised electrons

properties of metals

• good conductors of heat + electricity

• malleable and ductile

• shiny ( lustrous )

• high melting and high boiling points

metallic bonding explained

atoms closely packed together, energy shells next to another, overlap, can flow freely Among other atoms
-can be positive if lose an election, or negative if gain
therefore positive nucleus is attracted to surrounding electrons of other atoms and causes metallic bonding