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combines the negatively charged bond is formed, like in table salt
-
chlorine atom (Cl ) (NaCl). When the atoms share the
and the positively electron(s), a covalent bond is
charged sodium atom formed. Electrons aren’t perfect,
+
(Na ) together to though, and usually an electron is
form NaCl. more attracted to one atom than
another, which forms a polar
covalent bond between atoms (like
Types of Chemical Bonds A
in water, H 2O).
molecule is the smallest unit of a
While it may seem a bit random
compound that still has the
right now, with a little bit of study,
compound’s properties attached to
you’ll find you can soon understand
it. Molecules are made up of two or
how molecules are formed and the
more atoms held together by
shapes they choose once you
covalent bonds.
figure out the types of bonds that
Ionic compounds aren’t really real can form. Let’s take an example:
molecules. When ionic compounds
Why does ice float? In the water
are solids, they are really a
molecule (H 2O) is held together by
structure of charged particles.
polar covalent bonds. Water
In the space where electrons from
molecules are also attracted to
different atoms interact with each each other by weak (hydrogen)
other, chemical bonds form. The bonds between the atoms. As
electrons in the outermost shell are
water cools below 4°C, the
the ones that form the bonds with
hydrogen bonds forms a hexagonal
other atoms. crystal lattice (known as 'ice'). The
Since electrons are all negatively solid form of water is a larger
charged, they repel each other. structure than the
However they are attracted to the liquid form, as the
protons in the nucleus within crystal structure
atoms. How they choose to stick has a hole in the
together and interact is what center. In other words, ice takes
chemical bonds is all about. up about 9% more space than
liquid water, so a liter of ice weighs
There are two main types of bonds
less than a liter water. By peeking
that form between atoms: ionic
into the molecules closely, you can
bonds and covalent bonds. When
explain why ice is one of the very
one atom accepts or donates an
few solids that is lighter than its
electron to another atom, an ionic
liquid form.
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