Dissolving in water - links to information
Water molecules
Water molecules are polar, they have positive and negative
Charges at different ends of the molecule.
The hydrogen end is positive and the oxygen end is negative.
A water molecule is about 0.3 nm in diameter - very small!
Sugar - sucrose molecule
Sucrose molecules are made up of carbon,
hydrogen and oxygen.
Where there are hydrogen and oxygen
atoms, there are positive and negative
charges, just as in water molecules.
A salt (NaCl) crystal lattice:
A crystal lattice is formed by
the positive and negative ions. This
forms square-shaped crystals and
about 1 or 2 nm in size.
Units
What is a nanometer (nm)? There are 1000000 nm (million) in 1 mm. Look at 1 mm on your ruler
and imagine dividing that distance into 1 million divisions. The above structures are very small !
Polar molecules and dissolving A list of links that will be useful to your Chemistry course and for
your homework.
Properties of water : https://www.youtube.com/watch?v=aVmU3CLxvgU
Dissolving salt and sugar:
Chapter 5 - Lesson 1, 3 and 4
http://www.middleschoolchemistry.com/multimedia/chapter5/lesson1