Chemial Bonding Flashcards
general physcial properties of simple molecular substances
low melting point and low boiling point
cannot conduct electricity
insoluble in water
soluble in organic solvents
Y do simple molecular substances have the term simple in front
“simple molecular substances” refers to substances made up of molecules containing only a few atoms bonded together
its also to contrast to other names like “ giant covalent structures”
Small molecules make up the structure of simple molecular substances.
T/F
true
Molecules are particles made up of non-metal atoms joined together by strong covalent bonds. The size of each molecule in simple molecular substances is small because each molecule is made up of only a few atoms joined together. For example, a water (H2O) molecule is made up of only three atoms and a hydrogen (H2) molecule is made up of only two atoms.
Strong covalent bonds hold the atoms in the small molecules together.
T/F
True
Molecules in simple molecular substances are made up of a few non-metal atoms joined together through the sharing of electrons which results in strong covalent bonds.
Weak forces of attraction hold the small molecules together.
T/F
true
There are many small molecules in a simple molecular substance and weak forces of attraction exist between these molecules to hold them together in the substance.
When simple molecular substances change state, the molecules are usually not changed. Therefore the chemical formula of water is H2O regardless of its form (e.g. ice and water vapour).
properties of giant molecular substances
high melting and boiling points.
They generally do not conduct electricity.
y do simple molecular substances have low melting point and boiling point
Simple molecular substances have relatively low melting and boiling points due to the weak forces of attraction between the molecules that require a small amount of energy to overcome.
What are Van der Waals forces of attraction
Van der Waals forces of attraction are relatively weak attractive forces that act on neutral atoms and molecules of the same type. These forces originate because of the electric polarization induced in each of the particles by the presence of other particles.
What is electronegativity
It’s how much a molecule wants the electrons in a covalent bond
What’s partial positive/negative charge
It’s due to the uneven sharing of bonds in the bond as one side is more electronegative than the other and attracts the electrons to it
The more electronegative atom with the electrons will have a partially negative charge as electrons r negative and the opposite is true
