Bonding Flashcards
(23 cards)
What is an ionic bond?
It is the electrostatic force of attraction between oppositely charged ions formed by electron transfer.
What are the forces between ionic compounds?
electrostatic forces of attraction
What is covalent bonding?
Two non-metals share a pair of electrons
What is dative covalent bonding?
It forms when a nonmetal atom donates a lone pair of electrons to form a covalent bond with another atom.
What is metallic bonding?
It is the electrostatic force of attraction between the positive metal ions and the sea of delocalised electrons.
What is meant by malleable?
It can be beaten into shape
What is meant by ductile?
It can be pulled into thin wires
The strength of the metallic bonding depends on what?
NO OF PROTONS AND DELOCALISED ELECTRONS
- more = stronger bond
SIZE OF THE ION
- smaller ions = electrons are closer to the nucleus = stronger bond
What is the structure of ionic compounds?
Giant Ionic Lattice
What are the structures formed in covalent bonding?
- Simple molecular structure
- Macromolecular structure
What is van der waals?
Electrons are moving constantly and randomly, forming an induced dipole.
What are instantaneous dipoles in van der waals? What can it do to other molecules?
When a dipole is formed temporarily and instantaneously due to random movement of electrons. They can cause an induced dipole to form in neighboring molecules.
_________ number of electrons, stronger ______ van der waals
Increased number of electrons = stronger force
What will increased number of electrons do in van der waals?
It will increase boiling point and make the forces between the molecules stronger.
What is permanent dipole-dipole forces?
It occurs between molecules that have a polar bond/permanent dipole.
What is hydrogen bonding and how can it occur?
Interaction between a hydrogen atom attached and three most electronegative element such as N, O, & F. High boiling point.
What are the properties of ionic compounds?
- high melting and boiling points
- soluble inwater
- conduct electricity when molten, dissolved, or aqueous due to free moving ions.
Why does diamond and graphite have very high melting points?
Because they are giant covalent structures that have strong covalent bonds.
What are the properties of metals?
- when solid/liquid, good conductor of electricity
- do not dissolve
- high melting/boiling points due to strong metallic bonds
What is a simple molecular structure?
Structures joined by strong covalent bonds but weak IM forces.
What is a macromolecular structure and what are examples of this?
GIANT COVALENT STRUCTURES that have high melting points due to many strong covalent bonds (e.g. diamond and graphite)
Where do van der waals occur?
They occur between all simple covalent molecules and the separate atoms in noble gases (but not in ionic substances).
Why do lone pairs affect the bond angle?
Lone pairs repel more than bonding pairs and so reduce bond angled
