3.1.3 Bonding Flashcards
What shape molecule has two bonding pairs and no lone pairs?
Linear
What shaped molecule had 3 bonding pairs and 0 lone pairs?
Trigonal planar
What shaped molecule had 2 bonding pairs and 1 lone pair
Bent (v- shape)
What shaped molecule is 4 bonding pairs and 0 lone pairs?
Tetrahedral
What shaped molecule has 3 bond pairs and 2 lone pair of electrons?
Trigonal pyramidal
What shaped molecule had 2 bonding pairs and 2 lone pairs of electrons?
Bent (v- shape)
What shaped molecule has 5 bonding pairs and 0 lone pairs of electrons?
Trigonal bipyramidal
What shaped molecule has four bonding pairs and 1 lone pair of electrons?
Trigonal pyramidal/ seesaw
What shaped molecule has 3 binding electrons and 2 lone pairs?
Trigonal planar/ t- shape
What shaped molecule has 6 bonding electrons and 0 lone pairs?
Octahedral
What shape has 5 bonding pairs and 1 lone pair?
Square pyramidal
What shaped molecule has 4 bonding pairs and 2 lone pairs of electrons?
Square planar
What is the definition for electron negativity?
How easily an element it functional group can attract electrons
What are the four most electronegative elements?
Fluorine
Oxygen
Nitrogen
Chlorine
In ionic bonding, what charge does the non metal have?
Negative
What force attracts positive and negative ions?
Electrostatic attraction
What are three properties of ionic compounds?
High melting point
Poor electrical conductivity (unless molten or dissolved)
Soluble in polar liquids eg water
What does covalent bonding occur between?
Non metals and non- metals
What is the definition for a covalent bond?
The electrostatic force of attraction between shared electrons and the neucleus
What is the octet rule?
Where r bonded atoms achieve 8 electrons in the outer shell to achieve stability
Which diagram can present a covalent bond?
Dot and cross diagram
What are the five exceptions of the octet rule? (And how many electrons do they have instead)
Boron Triflouride (six)
Sulfur hexaflouride (12)
Phosphorus Pentachloride(10)
Chlorine Triflouride (6)
Sulphur Tetrafluoride (8)
What is the definition for dative covalent bonding?
A covalent bond in which both shared electrons come from the same atom
How is a dative covalent bond shown in a stick diagram?
An arrow pointing at the atom that is not sharing any of its own electrons
What two structures can covalent structures be found?
Simple molecular
Giant covelant
What is the definition for electronegativity?
The ability of an atom to attract bonding electrons in a covalent bond
What is a permanent dipole?
Where there is a small charge difference across a molecule but not enough for an ionic bond
Why might a molecule with polar bonds not be polar?
It is symeytrical
What is polarity determined by
The shape of molecule and electronegativity of atoms
What force is responsible for melting and boiling point ?
Intermolecular
What do covalent bonds effect?
Chemical reactions
What is a vanderwaal force?
A force between all molecules caused by induced dipole-dipole interactions.
How does an induce dipole-dipole interaction occur?
Electrons move to one side of molecule
Creates a slight charge difference across molecule
Attracts the electrons of the molecule next to it and the one next to that ext.
T or F:
Polar solute is soluble in polar solution
T
Why can polar substances not dissolve in non-polar substances?
They have a different strength of intermolecular forces (permanent and induced dipole interactions) so the permanent dipole interactions can’t be broken by the induced dipoles therefore they cannot dissolve
What three bonds allow for hydrogen bonding?
N-H
F-H
O-H
Why does hydrogen bonding occur
The electrons from the hydrogens in a F-H, N-H or O-H move away from the hydrogen creating a dipole, this causes the hydrogen to attract the lone pair of electrons from another O, N or F atom.
What property of water is unusual due to hydrogen bonding
Ice is less dense that water
What is the definition for metallic bonding?
A lattice of closely packed, positive ions in a sea of delocalised electrons
What element has the highest melting and boiling point on period 3? And why
Silicon, it forms a covalent lattice which means that it needs to have its covalent bonds broken before it can be melted.
What three types of bonding occur in period 3and with what elements?
Metallic bonding- sodium, magnesium, Aluminium
Giant covalent- silicone
Simple covalent- phosphorus, Sulfur, chlorine
Name the elements in period 3
Sodium
Magnesium
Aluminium
Silicon
Phosphorus
Chlorine
Argon
