Thursday, May 20, 2010

Elements, Mixtures & Compounds!

Today in class we had Mr. Tim as our teacher because Ms. D went on a field trip with the 7th graders.Mr. Tim discussed elements, compounds, and mixtures to us.

An element: a substance which cannot be broken down into other substances by ordinary chemicals. Each element is represent by a symbol. Example: oxygen = O , gold = Au, helium= He

Here is a link to "The Element Song"

A compound: two or more elements can be combined to form compounds. Compounds are very different from the elements from which they are formed. Example:NaCl, made from sodium, a dangerous and explosive element, and chlorine, a poisonous gas.

A mixture: made from two or more substances, elements, compounds, or both in definite proportions, and these proportions are not always the same. Example: soil, cake, milk

Homogeneous mixture: the substances in a homogeneous mixture are so evenly mixed that you can't see the different parts. Example: cake batter, petrol, plastic spoon

Heterogeneous mixture: in a heterogeneous mixture you can see the different parts. Example: salad, gravel, car

After discussing those topics, we reviewed temperature, weight, mass, volume, and density. We gave a definition, units, and the equipment used for each property.

Temperature: - a measure of the average NRG of motion of the particles of a substance
- Celsius and Kelvin
- thermometer
Weight: - a measure of the force of gravity on an object.
- Newtons, kilograms
- force scale, spring scale
Mass: - a measure of how much matter is in an object.
- kilograms
Volume: - the amount of space that matter occupies.
-centimeters cubed
-ruler, graduated cylinder
Density: - the measurement of how much mass of a substance is contained in a given volume
-TBB, ruler

Finally we got to our rotation lab on matter. In this lab we had to smell and examine 12 different substances and write down their symbol/formula, their physical properties, decide if the substance was a solid, liquid or gas and decide if it was an element, compound or mixture.

Here are some substances that were examined: .
  • Copper- Cu, solid, element
  • Hydrogen peroxide- H2O2 , liquid, compound 
  • Rubbing Alcohol-C3H8O, Liquid, compound
The homework from today is to complete "States of Matter-pg 42-47" and by reading those pages fill out States of Matter Note Taking Section in our Chemistry Packet.
Also don't forget another blog comment is due tomorrow (Friday).

The next scriber is Alex.


  1. Hi Holly,

    I think that this is a very thought-out post with good definitions of the words, and I liked the table of the elements, but I think that you could have used even more colors and not light green - It is a bit TOO light. You could have added a picture of a mixture, too.
    But other than that, great job!

  2. Hi Holly!
    Overall I liked your scribe post. The definitions of the vocabularies were very clear and I was able to review some of my vocabularies as well. We also learned about the Periodic Table of Elements when I was in 6th grade. I liked it that you emphasized some of the words; however, next time you should BOLD all of your words. You could have emphasized certain words such as Temperature, Weight, Mass, and Volume. Then your scribe post would have looked more organized. Also try to avoid using light green as your text color because it is rather hard to see. Once again, I really enjoyed looking at your scribe post.

  3. Holly - Your post definitely covers all of what you did during class. Plus it does so with good spelling, grammar and sentence structure. You have scientific vocabulary throughout and have explained it well. Your link to the "Elements Song" is helpful and your Periodic Table looks good. The one area you forgot to do was a real-life relationship; the newest requirement for blogging during the fourth quarter. Also, I think you could have included more colors for your font. The purple was a bit overwhelming and did not help differentiate different parts of the class (lab from physical properties from elements/compounds/mixtures). Overall though this is a thorough and well organized post. ~Ms. D.

  4. Hey Holly,

    Very nice job on your scribe post, I liked it that you made the font colorful and thank you for the picture. I thought the song was funny and a little bit hard to understand. I also liked it that u included all the definitions of vocabulary we learned in class and the different equipment we use in the lab to measure different things like mass and density, I just hope I would have looked at it before the quiz… you could have explained a little bit more about the Periodic Table, but after all you did a great job!

    Abigail :D