Elements are mainly classified into metals & non-metals. State six properties of metals which differ from non-metals.

Give the symbols of the following elements and state in each case whether they are metals, non-metals, metalloids or noble gases.

a) Potassium
b) Carbon
c) Oxygen
d) Mercury
e) Fluorine
f) Neon
g) Sulphur
h) Zinc
i) Boron
j) Copper
k) Calcium
l) Xenon
m) Arsenic
n) Mercury
o) Chlorine
p) Silicon
q) Neon
r) Lead
s) Antimony
t) Sodium
u) Iodine
v) Platinum

w) Radon
x) Phosphorus
y) Bromine
z) Aluminium.

Write the symbols of the following elements & radicals along with their valencies.

(i): Sodium
(ii): Magnesium
(iii): Chlorine [chloride]
(iv): Nitrate
(v): Sulphite
(vi): Aluminium
(vii): Oxygen [oxide]
(viii): Bromine [bromide]
(ix): Zinc
(x): Sulphur [sulphide]
(xi): Sulphate
(xii): Hydroxide
(xiii): Calcium
(xiv): Carbonate
(xv): Potassium
(xvi): Phosphate
(xvii):Iodine [iodide].

Valency list: i]$1^{+}$ ii] $2^{+}$ iii] $3^{+}$ vi] $1^{-}$ vi] $2^{-}$ vi] $3^{-}$.

Write the chemical formula of the following.

Sodium bromide