Chapter 3 - Bonding Flashcards
What two types of elements are required for an ionic bond?
One non-metal and one metal
What is another name for a positive ion?
A Cation.
What is another name for a negative ion?
An Anion.
What is the name of the attraction between oppositely charged ions in an ionic bond?
Electrostatic.
Do ionic compounds have high or low boiling points?
High booking points.
Are ionic compounds soluble or insoluble?
Soluble.
Can solid ionic compounds conduct electricity?
No they can only conduct electricity when they’re molten or aqueous.
Do metal ions lose or gain electrons when bonding ionically?
Lose
Define metallic bond.
The metallic bond is the attraction between the positive metal ion and the free electrons.
Why can metals conduct electricity?
Because their delocalised electrons can move freely, they can carry energy.
What is a covalent bond?
A singular covalent bond is a shared pair of electrons, one from one atom and one from the other.
Why are metals malleable?
Because layers of metal ions can slide without breaking the electrostatic attraction.
What is a dative covalent compound?
A covalent bond where both of the electrons in the shared pair are supplied by one atom.
What are the three forces between covalent molecules?
1) Van der Waals
2) Permanent dipole dipole
3) Hydrogen bonds
Which of these forces takes the most energy to break?
The hydrogen bonds.
When do Van der Waals forces exist?
Between all simple covalent molecules and is the only force between two atoms of equal electro negativity.
What is the most electronegative element on the periodic table?
Fluorine.
When are permanent dipole dipole forces present?
Between two atoms which are non-polar (have slight charges/ different electro negativity)
What is the difference between polar and non-polar molecules?
Polar molecules have NO charges and therefore, equal electronegativity
Non-polar molecules HAVE charges because they have different electronegativity.
What is a temporary dipole?
When the majority of electrons randomly move to one side of the atom giving it a slight charge for a short time.
What is an induced dipole?
When originally non charged molecules get a charge because a neighbouring molecule had a temporary dipole.
When do hydrogen bonds occur?
Hydrogen’s are only present in bonds between Hydrogen and one of:
Nitrogen
Oxygen or
Fluorine
What are lone pairs?
A lone pair is a pair of electrons that are not used in (left over after) covalent bonding.
