DK - WOW! The Visual Encyclopedia of Everything

Oxygen atom

93

◀ WATER (H 2 O)

When two atoms of the gas

hydrogen (H) bond with one atom

of the gas oxygen (O), they form

molecules of liquid water. Water

is the most common compound

on Earth and is essential for life.

▲ AMMONIA (NH 3 )

The colourless gas ammonia is made

up of one nitrogen (N) atom bonded

to three hydrogen (H) atoms. Plants

get the nitrogen they need to grow

from ammonia and other nitrogen

compounds within the soil.

◀ DIAMOND (C)

A diamond can be thought of as a

single giant molecule. It is formed from

atoms of carbon (C) bonded in a strong

crystal lattice. However, if carbon atoms

join in flat sheets of hexagonal tiles,

they form graphite, a brittle substance

used to make pencil leads.

SULFUR (S 8 )

Eight atoms of sulfur (S)

bond together in a ring

to form a sulfur molecule.

Most non-metal elements

are gases at room

temperature, but sulfur

is a brittle, yellow solid.

Hydrogen atom

Nitrogen atom

Hydrogen atom

Carbon atom

Except at the edges,

each atom is linked

firmly to four others

Sticks are used to

show the bonds

between atoms

Sulfur atom

Balls represent

atoms in models

of molecules

092_093_Molecules.indd 93 03/01/19 12:10 PM