Chemical Bonding Flashcards
What is a compound?
Compounds are made up of atoms of more than one
element. Energy is required to separate the elements in
a compound because the different kinds of atoms are
chemically joined.
What is the chemical joint between atoms in a compound called?
The chemical join between different atoms in a
compound is called a bond.
What are ionic bonds?
Ionic bonds are made between a metal and a non-metal. An ionic bond is the electrostatic force of attraction
between oppositely charged ions.
What are covalent bonds?
Covalent bonds are made between non-metals only. A covalent bond happens when the positive nuclei from two different atoms are held together by their common attraction for the shared pair of electrons held between them.
What is metallic bonding?
Metallic bonding is between metals only, always positive charge.
Do metal atoms lose or gain electrons?
Metal atoms lose electrons to form positively charged ions.
Do non-metal atoms lose or gain electrons?
Non-metal atoms gain electrons to form negatively charged ions.
What structure are Ionic compounds comprised of?
Ionic compounds such as sodium chloride, exist as giant lattices of ions . Formula such as NaCl give the ratio of ions present in the lattice.
What are the physical properties of ionic bonds?
- High melting point solids due to strong ionic bonds between positive and negative ions in lattice structure.
- Conduct electricity
- They conduct when dissolved in solution or molten as the ions are free to move .
- Dissolve in water
Potassium bromide is an ionic compound. How would an ionic bond be formed?
1) Transfer of electron from K to Br
2) Formation of ions K+ and Br-
3) Forms lattice Structure
4) Strong electrostatic forces hold structure together.
What is the Octect Rule?
Covalent compounds share electrons to become more stable.
-Octet Rule (2 or 8 electrons in outer shell)
-Noble gas arrangement
Why do Noble Gases not bond?
They have stable outer shells - 2 ( Helium) , 8 outer electrons for the others.
What is a covalent molecular bond?
A discrete group of atoms (you can count the atoms) held together by covalent bonds is called a molecule.
What does diatomic mean? List all known diatomic molecules.
Molecules made up of only two atoms are called diatomic ( two atoms).
Fluorine - F2
Chlorine - Cl2
Oxygen - O2
Hydrogen - H2
Nitrogen - N2
Bromine - Br2
Iodine - I2
What are some discrete covalent molecular structures?
Linear, angular, pyramidal, tetrahedral.
What are fullerenes?
These are discrete covalent molecular substances such as carbon nanotubes, C60 (spherical fullerenes, also known as buckyballs.)
What are the covalent molecular physical properties?
- Low melting and boiling points
- Does not conduct electricity
- Generally do not dissolve in water
What is a covalent network?
Covalent substances that are solids with high melting points have much larger molecules. A covalent network substance consists of a giant lattice of covalently bonded atoms. Examples are diamond, graphite and
silicon dioxide.
