OSA

Omid Eghbal, Sami Freeman, Angie Petit-Frere

**chemical property** - a characteristic, when measured or observed, changes the chemical make-up of the original substance.

**Flammability**- is a chemical property.

**physical property**- any property used to characterize matter and energy and their interactions.

Physical properties are color, smell, boiling point, freezing point, etc.

**homogeneous** - a substance or material that contains only one kind of compound or one element.

Blood, soapy water, salt water, are examples of homogenous mixtures.

**heterogeneous**- a mixture or substance composed of different substances or the same substance in different phases, such as solid ice and liquid water.

Examples or heterogeneous mixtures are oil and water, and orange juice with pulp.

**suspension** - a state in which the particles of a substance are mixed with a fluid but are undissolved.

Mud or muddy water, snow globes, and paint dust are examples of suspensions.

**solution** - a homogeneous, molecular mixture of two or more substances.

Lemonade, Iced tea, Fruit Punch, are examples of liquid solutions.

**density** - mass per unit volume.

Density is used to measure the mass in the volume of liquids.

**filtrate** - material, especially liquid, that has passed through a filter. Example: Coffee filter to separate the coffee from the coffee ground not wanted.

**atom** - the basic unit of matter that consists of a dense, central nucleus surrounded by a cloud of negatively charged electrons.

The basics we know about atoms is that it contains protons, and neutrons, which can also be called electrons.

**element** - a chemical substance consisting of one type of atom distinguished by its atomic number. As of September 2011, there are 118 elements that have been identified.

We know that the elements are listed on the periodic table. Examples of elements we know are brass, nickel, nitrogen, carbon, oxygen, etc.

**molecule** - the smallest physical unit of an element or compound, consisting of one or more like atoms in an element and two or more different atoms in a compound.

Water molecules make up water, CO2 molecules make up carbon dioxide, ethanol molecules make up ethanol, etc.

**compound** - a substance composed of two or more elements whose composition is constant.

Compounds we know of are Carbon Dioxide, Sodium Chloride, etc.

**physical change** - a usually reversible change in the physical properties of a substance, as size or shape.

For example, freezing water to ice, or melting ice to water.

**chemical change** - a usually irreversible chemical reaction, involving the rearrangement of the atoms of one or more substances and a change in their chemical properties or composition, resulting in the formation of at least one new substance.

Burning paper, Rusting Iron, and exploding of fireworks are a few examples I know of chemical change.

Oberservations:
== STEP 1:The top is the lightest color out of all three. The bottom portion is the most dense. We think the top is section is vinegar and middle of ours is oil and the bottom is either, dirt or tobacco. == == STEP 2: After the separation, the liquid became lighter without the oil. It is now less thick because the oil was the really thick area. The brown pieces stayed at the bottom. Even with the oil gone, the water is not completely back to normal and thin again. ==

Analysis:
Identification of impurity removed with each step of purification - based on your observations and on what you found each material is //supposed// to remove.


 * Before the treatment, the water __solution,__ which was __heterogeneous__ had a volume of 200 ml, with three different colors. It was a __suspension__ with a top layer, which consisted of the oil, with the lightest color of the three. Each layer is a bit darker then the layer on top. This water had some pieces of dirt, garlic, or tobacco, which remained in the bottom layer, which was the most __dense__ section that had the most __atoms__. As we observed this mixture, it had 100 percent of it's solution left.
 * After the oil water separation the liquid has a volume of 171 ml. This means that we had about 85.5 percent of the solution left. We saw that It is not as dark as it was before. It separated the water from the oil from the solution. The mixture is not as thick, and the dirt, tobacco, or garlic is still in the bottom layer. Even with most of the oil gone, the water is not as thin as one would expect. The oil water separation (which was supposed to separate the oil from the water) didn't do it's job well, there is still oil left in the water.
 * After the sand filtration, the water has a __volume__ of 135 ml, which means that there is 79% of the solution left. There is a shade of light yellow and the oil is completely gone. The liquid now resembles water more than before. Yes, it seems that the sand filtration (which is supposed to clean out the oil and little black particles of the garlic and tobacco) did it's job well. The water still reeks of garlic.
 * As it passes through the charcoal filter, the __filtrate__ now resembles clean water and has little to no smell of garlic. This charcoal ( which is supposed to clean out the color, and the smell) did it's job well. Due to timing we were left with about 53.5 ml of water, which meant there were about 39.63 percent of the solution left.
 * Out of all of the __elements__ together, there was no __chemical changes__ but there were many __physical changes__, such as the color changes and the thickness of the __compounds.__

During our experiment we had five steps to make our water pure. During the first step nothing was removed from the liquid. After the second step, oil was removed from the liquid using a pipet. The third step helped remove the odor, which was a __physical property__; we believe this scent was garlic. The fourth step helped remove the vinegar, a __homogeneous__ liquid. It made the water more clear and one-step closer to being purified. The fifth step helped remove the charcoal. The liquid was not __flammable,__ so it did not have that __chemical property.__