A Visual Encyclopedia of the Periodic Table

154

The Nitrogen Group

15

Nitrogen surrounds us all the time because

it is the transparent gas that makes up

nearly three-quarters of Earth’s atmosphere.

Since pure nitrogen does not react easily,

its liquid form can be used to freeze and

preserve items such as blood and tissue samples.

Nitratine is one of the few minerals rich in

nitrogen. Some useful nitrogen compounds

can be made by industrial processes. A group

of nitrogen compounds is used in explosives,

including TNT and nitroglycerine. When

ignited, they explode because the bonds

Nitrogen 7 7 7 State: GasDiscovery: 1772

N

7

Nitratine

This is a naturally

occurring form of

sodium nitrate.

Microscopic image

of root nodule

Bacteria living

inside plant roots

can take nitrogen

from the air for

use by the plant.

Saturn’s largest

moon has an atmosphere

containing 48% nitrogen.

Ti

tan

This clear and

colourless liquid

forms when nitrogen

is cooled to below

–195°C (–319°F).

Forms

Pure n

itro

gen

(^) in
(^) a
gl
as
s
sp
he
re
Nitrogen gas gives
off a purple glow
when electrified.
Liquid^ nitrogen
Pure nitrogen gas
is trapped inside
this glass sphere.
154-155_Nitrogen.indd 154 12/12/16 5:40 pm