Monday, August 31st, 2009

First I want to say that teacher is kind of frustrating I don't know, is just my opinion, and I really needed to say it, I know students are too, but oh just anyways, that is just my opinion. And to say I was really paying attention
Let's talk about the real journal the thing that really matters, during last class we were talking about matter and its properties, It divides into General Properties and Specific properties.\

Matter Properties.

General Properties: They are common to all kinds of matter.

Volume: Space that matter occupies.
Mass: Ammount of matter contained in a body.
Inertia:Opposition that a body presents to change its movement or its static state.
Weight: Measure of force of attraction between objects due to gravity
Elasticity: When bodies can be temporarily deformed by an external force.
Impenetrability:Two bodies can't occupy tha same space at the same time.
Porosity: All bodies present spaces between particles.
Divisbility: All bodies can be decomposed by mechanical or energetical means.

Specific Properties: Helps to identify a substance from another one.
It can be divided into Physical and Chemical.

Physical property: It can be measured and observed without changing its composition or identy of a substance.

• Changes can be reversible.
• Nothing is used up.
• Nothing is formed.

Chemical properties: Refers to a characteristic that matter exhibits as it undergoes a change in its composition.

• One or more substances are consumed.
• One or more sibstances are formed.
• Energy is absorbed or released.

EXAMPLES.
Physical: State of matter, Odor, density, temprerature, melting point, boiling point.
Chemical: Reactivity, acidity, vapor pressure, solubility, thermal stability, oxidand strength, reductant strength.

Properties can also be classfied on the basics of whether they depend on how much of matter is present.

Extensive properties: Are dependamnt upon the ammount of substance present.
Example: Mass, Volume.

Intensive properties: Are independant of the ammount of matter.
Example: Color.

Okay, my opinion about this, classes are starting to be boring, I mean, I understood it, but if we always do the same it kinda make me feel sleepy or anything, anyways, this topic I think I understood it very well.

Energy.
It is the capacity to do a work.

Energy can be presented into two states:

Kinetic or movement energy: Energy of a body because of its movement.
Example: Waterfalls.
Potential or stored energy: Energy of a body because pf its position.
Example: Water stored in a dam.


Conservation Laws.
Matter conservation Law: Mass is neither created or destroyed, just transformed. -Antoine Lavoisier.
Energy conservation Law: Energy is neither created or destroyed, just transformed. -Robert Mayer.
Mass-Energy conservation Law: The ammount of mass-energy that is present in the universe is constant. -Albert Einstein.

Kabick Tam