Bonding
A bond forms when two things stick
together. What bonds can you think
of? You can use glue to bond many
different items together. Two
magnets form a kind of bond when
they stick together. Welders use
special tools to bond pieces of metal
together. Some bonds are very
strong, and some are not so strong.
Atoms, the building blocks of
matter, can also bond to each other.
Atoms form bonds when they
combine in special ways.
A compound forms when atoms of
two or more different elements bond
together. Some bonds between atoms
are very strong, but some are much
weaker. Some elements can make
many bonds at once. Every atom of
carbon, for instance, can make four different bonds
with different atoms.
When atoms bond together, their properties change. The
compounds they make have different properties from the original
elements. For example, water is a compound made from hydrogen
and oxygen. Hydrogen and oxygen are both gases at room
temperature. Water is a liquid at room temperature. Hydrogen and
oxygen both burn easily, but water does not.
Some compounds, like water, salt, and carbon dioxide, are made
of only two different elements. Salt is made of sodium and chlorine.
Carbon dioxide is made of carbon and oxygen.
Some compounds are made of many different elements. For
example, chlorophyll is made of five different elements: carbon,
nitrogen, hydrogen, oxygen, and magnesium. These five elements
bond together to make a compound that helps plants make food.
Discovery Education Science
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