chapter 2-matter (part 1)

• Physics is the study of both matter and energy, in an attempt to understand how the physical world around us works. Matter is what everything is made of. 

• Matter can be either a solid, liquid or gaseous state. Any substance made from matter will take one of these forms, however, substances can readily change states with the addition or removal of energy. 

• An example of this is water, which at room temperature is liquid, but becomes a solid (ice), when cooled (energy removed) but can also become a gas (steam) when heated (energy added).

Slides below show you the outlines for this chapter:

First, let us look on definition of matter and conservation of matter:

Atoms are made up of a central core (Nucleus) which is made up of two types of particle: The Proton, which carries a positive electrical charge and the Neutron, which is electrically neutral. Both Protons and Neutrons have nearly the same mass 1.67 x E27Kg.

The electrons are arranged in energy levels or shells around the nucleus and with increasing distance from the nucleus. The shells are lettered from the innermost shell outwards from K to Q. There are rules about the maximum number of electrons allowed in each shell.

If the orbit number is “n”, then the maximum electrons held in the orbit is given as 2n^2.

The valance orbit of any atom is the outer most orbit (shell) of that atom. The electrons in this valance orbit are known as valance electrons. All atoms desire to have their valance orbit completely full of electrons, and the fewer valance electrons in an atom, the easier it will accept extra electrons.

In Part 2, You will be informed about compound, bonding and states of matter.