Group 18 (noble gas)
Group 1(alkali metal)
Group 17 (Halogens)
He, Ne, Ar, Kr, Xe, Rn, Og
H, Li, Na, K, Rb, Cs, Fr
F, Cl, Br, I, At, Ts
Physical properties
- colourless & odourless gas
- insoluble in water
- x conduct heat & electricity
- has low boiling point &
density
Physical Properties
- grey solid and shiny
- conducts heat & electricity
Physical Properties
- have dull surface
- x conduct electricity in all
states
- low melting & boiling points
- diatomic atoms
going down group 18
- increasing atomic size
causes Van der Waals
attraction to be stronger,
higher boiling point
- density increases
going down group 1
- atomic size increase causes
strength of metallic bond to
become weaker
- more reactive
- more electropositive
(releases electron easier
because valence electron is
further from nucleus)
going down group 17
- molecular size increases,
causing intermolecular Van
der Waals attraction to
become stronger. higher
melting and boiling point.
- colour of halogens is darker
- less reactive
- more electronegative
(the nuclear attraction force
becomes weaker, strength to
pull one electron to outermost
shell decreases )
- x donate, receive or share
electrons w other atoms
- monatomic atom and
chemically inert bcoz have
stable octet/duplet
arrangement
+ water → alkaline solution
and hydrogen gas
+ oxygen → metal oxide
+ chlorine → metal chloride
+ water → acid
+ iron → iron (III) halide
+ alkali → two different halide
.
salt + water
Lithium, Sodium, Potassium
Chlorine, Bromine, Iodine
Electropositive - tendency of an atom to donate its valence electron and form metal cation
Electronegativity - tendency of a non-metal atom to receive electrons in its outermost shell and
form anion
Period 3
Na, Mg, Al (group 13), Si, P, S, Cl, Ar
Changes in physical properties
- number of protons in the nucleus increases
- positive charge in the nucleus increases
- atomic size decreases
(nuclear attraction toward electrons in three shells becomes stronger, m electrons are pulled
towards nucleus)
Oxide
compound
Type of
oxide
Na₂O
Al₂O₃
MgO
Metal oxide
SiO2
P4O10
SO4
CL2O7
Non-metal oxide
Basic oxide
Amphoteric oxide
Acidic oxide
- Reacts with acid
to produce salt
and water
- reacts with acid
and alkali to
produce salt and
water
- reacts with alkali to produce salt and water
TRANSITION ELEMENTS
-
Metallic elements located in group 3 to 12
All transition elements exhibits metallic properties
Special characteristics of transition elements
- have more than one oxidation no.
- can form coloured ions and compound
- can form complex ions
- acts as catalyst in chemical reactions
Uses of transition elements in industries
- iron as catalyst in haber process to produce
ammonia
- platinum as catalyst in Ostwald process to
produce nitric acid
- vanadium (V) oxide as catalyst in contact
process to produce sulphuric acid
- nickel as catalyst in hydrogenation to
produce margarine from vegetable oil