MODULE 3
12
WORKSHEET
WORKSHEET
WATER AS A SOLVENT
Syllabus reference 8.4.3
1
Classify each of the following statements as true or false. For the statements that are false
rewrite them so they are true.
a
Covalent molecular substances are very soluble in water.
FALSE
b
MOST covalent molecular substances are INsoluble in water.
Most ionic substances are soluble in water.
TRUE
c
Another name for water solutions is aqueous solutions.
TRUE
d
Water bound in an ionic substance is called water of binding.
FALSE
e
Water is a non-polar solvent.
FALSE
f
Water is a POLAR solvent.
Carbon tetrachloride (CCl4) is soluble in water.
FALSE
g
Water bound in an ionic substance is called water of CRYSTALLISATION.
Carbon tetrachloride (CCl4) is INSOLUBLE in water.
All large molecules will dissolve in water.
FALSE MOST large molecules THAT ARE HIGHLY STRUCTURED will NOT dissolve in water.
h
Silicon dioxide will not dissolve in water because of the strong covalent lattice structure of the
compound.
TRUE
i
The low solubility of oxygen gas (O2) in water is due to weak dipole–dipole forces between
solute and solvent.
FALSE The low solubility of oxygen gas (O2) in water is due to weak DISPERSION forces
between solute and solvent.
j
Sucrose dissolves well in water because it can form hydrogen bonds with water.
TRUE
Copyright © 2008 McGraw-Hill Australia
CONQUERINGCHEMISTRY PRELIM
MODULE 3 WS 12
2
The solubility of substances depends on the nature of the bonding in the solute compared to that in the
solvent. This is often generalised as ‘like dissolves like’. Explain what is meant by this generalisation.
Polar substances will dissolve in polar solvents and do not dissolve in non-polar solvents while
non-polar substances will dissolve on non-polar solvents but do not dissolve in polar ones.
3
Complete the following table.
SUBSTANCE
BONDING TYPE
SOLUBILITY IN WATER
SOLUBILITY IN HEXANE
ionic
soluble
insoluble
Glucose (C6H12O6)
molecular covalent
with O–H groups,
hydrogen bonding
soluble
insoluble
Iodine (solid)
molecular covalent,
non-polar
insoluble
soluble
Silicon
molecular covalent,
non-polar
insoluble
soluble
metallic
insoluble
insoluble
Cellulose
molecular covalent
with O–H groups,
hydrogen bonding
soluble
insoluble
Hydrogen chloride
molecular covalent,
polar
soluble
insoluble
Sodium chloride
Zinc
Copyright © 2008 McGraw-Hill Australia
CONQUERINGCHEMISTRY PRELIM
MODULE 3 WS 12