Objectives Describe how a compound differs from an

Objectives • Describe how a compound differs from an element. • Identify parts of a chemical formula. • Explain why chemical bonding occurs. • CLE 3202. 1. 7 Construct chemical formulas for common compounds.

Chemical Bonds

Types of Bonds A. Ionic Bonds 1. Atoms can gain or lose electrons in the outer energy level.

Ionic Bonds 2. When the number of electrons is different from the number of protons, the atom has an electrical charge.

Ionic Bonds 3. The name of this charged particle is ion.

Ionic Bonds 4. When an atom loses an electron, it becomes a positively charged ion. A superscript indicates the charge.

Ionic Bond 5. When an atom gains an electron, it becomes a negatively charged ion. + Na Cl

Ionic Bond B. An ionic compound is held together by the ionic bond – the force of attraction between opposite charges of the ions.

Ionic Bond-Transfer

Ionic Bond-Transfer

Ionic Bond 1. The result of this bond is a neutral compound.

Ionic Bond 2. The sum of the charges on the is zero. ions

Covalent Bonds C. Molecules are neutral particles formed as a result of sharing electrons.

Covalent Bond 1. A covalent bond is the force of attraction between atoms sharing electrons.

Covalent Bond 2. Atoms can form double or triple bonds depending on whether they share two or three pairs of electrons.

Covalent Bond 3. The covalent compound has a complete outer energy level.

Triple Bonds-Nitrogen

Water

H 2 O - Water Each hydrogen atom shares one of its electrons with the oxygen atom. All atoms have a complete outer energy level. The entire molecule is neutral

Covalent Bond 4. Electrons shared in a molecule are held more closely to the atoms with the larger nucleus.

Covalent Bond 5. A polar molecule has one end that is slightly negative and one end that is slightly positive, although the overall molecule is neutral.

Polar Covalent Bond Water

Covalent Bone 6. In a nonpolar molecule, electrons are shared equally.

Non-polar Covalent Bond Methane

What two types of atomic bonds form and how do they differ? Ionic bonds form when atoms lose or gain electrons; covalent bonds form when atoms share electrons.

Objectives • Describe how a compound differs from an element. • Identify parts of a chemical formula. • Explain why chemical bonding occurs. • CLE 3202. 1. 7 Construct chemical formulas for common compounds.

Alkali Metals

Alkaline Earth Metals

Boron Group

Nitrogen Group

Halogens

Noble Gases