2-4 ELEMENTS AND COMPOUNDS

Although today's lesson was cut short, we learned that...

Matter could be divided into:

• homogeneous- consists of only ONE visible component
• heterogeneous- consists of MORE than one visible component

We also learned...
The differences between an element and compund is that:

• Elements cannot be broken down into simpler substances by chemical reactions
• Compunds are made up of two or more elementsby chemical reactions.

Finally, we learned...
the difficulty of differentiating an element and compound

• One method> Electrolysis(process which splits the substance into its constituent elements)

http://www.youtube.com/watch?v=WB0Kr8VA-74 - For some reason, I couldn't get the EMBED for this video. But, enjoy!

That is all. Mr. Doktor is the best!

BY: Krizia Umali

What Matters?

We know matter commonly as 3 forms: Solid, Liquid, and Gas... and for the more intelligent/Star Wars Fanatic, there is also Plasma, which is a state of matter thats like gas and liquid. We learned the different boiling points for water, and the effects of each change.

We also learned of three different types of change in matter:

- Physical Change
- Chemical Change
- Nuclear Change

In physical change: matter is changed in shape or form, but no new substances are created. Chemical changes result in a new substance being formed. We did not learn so much about Nuclear change... yet.

That is all. Mr. Doktor is the best.

--- by JBATO

Test Time E Block

So today instead of a usual lesson we had our highly anticipated Unit Test ... yay!
Our test consisted of safety symbols, lab materials, conversion, and calculating percentage error. It consisted of us knowing our:

- Lab symbols
- Significant Digits
- Percent Error
- and our Conversion Units !


That is all. Mr. Doktor is the best.

--- by JBATO

(Thursday, Sept 17, 2009)

None of us were present for this class.
That is all. Mr. Doktor is the best.

-- by Jael Lumba

In today's lesson (Wednesday, Sept 16, 2009), we learned about dimensional analysis and graphing. Dimensional analysis is the technique of converting between units. An example would be changing kilograms to milligrams:

120 kg x 1000g/1kg x 1000mg/1g = 120 000 000 mg = 1.2 x 10 to the power of 8

We learned that by doing an equation like this, it will help us cancel out units not needed in order to find the needed unit.

Here's a youtube video I found with lots of example on dimensional analysis:

We also learned about the basics of graphing:
1. Title
2. Labeled axis
3. Correct scaled axis
4. Data plotted correctly
5. Best-fit line

This is a perfect example of a graph done for votes in Iran:

That is all. Mr. Doktor is the best.

-- by Jael Lumba

(lesson on Monday, Sept 14, 2009)

This class' lesson was the introduction of the International System of Units aka SI. We learned that it consists of 7 metric units. These include metres for length, kilograms for mass and weight, and metres cubed for volumn. We also learned the metric prefixes, which is a syllable attached to the beginning of a metric unit to make it larger or smaller. Examples would be:

- kilo- (k) which means 1000 and is 10 to the power of positive 3. (to make a unit larger)

and..

- milli- (m) which means 0.001 and is 10 to the power of negative 3. (to make a unit smaller)



That is all. Mr. Doktor is the best.

-- by Jael Lumba