11.1 – Why Atoms Combine
- The properties of compounds are generally different
from those of the elements they contain.
- A chemical formula for a compound indicates the composition
of a unit of the compound.
- Chemical bonding occurs because atoms of most elements
become more stable by gaining, losing, or sharing electrons.
11.2 – Kinds of Chemical Bonds
- Ionic bonds between atoms are formed by the attraction
between ions.
- Covalent bonds are formed by the sharing of electrons.
- Ionic bonding produces charged particles called ions.
- Covalent bonding produces units called molecules.
- The unequal sharing of electrons produces compounds
that contain polar bonds, and the equal sharing of electrons produces nonpolar
ccompounds.
11.3 – Chemical Risks in the Home
- Compounds that are toxic, corrosive, or flammable are
hazardous.
- People can protect their health and the environment
from hazardous compounds in the home.
11.4 – Formulas and Names of Compounds
- An oxidation number indicates how many electrons an
atom has gained, lost, or shared when bonding with other atoms.
- In the formula of an ionic compound, the element or
ion with the positive oxidation number is written first, followed by the
one with the negative oxidation number.
- The name of a binary compound is derived from the names
of the two elements in the compound.
- A hydrate is a compound that has water chemically attached
to the ions and written into its formula. |
