Lab+Reports

Samantha Atamian, Chelsea Brennan, Aubrey Postolakis, Megan Ruiz CP Chemistry Period 6 September 24, 2010 __ Foul Water Trial 1 __
 * Introduction** : The main goal for the contaminated sample of water is to filter the water so that it is clean enough to drink. However, the sample of water has two layers, which is believed to be oil and water. It also smells of garlic, which means the water also contains sulfur. Also, there is evidently dirt floating around in the water. In order to filter this contaminated water, the hypothesis, if the water is boiled then the condensed and evaporated water will be separated from the oil, was formed for the experiment for trial one. However, oil cannot be put near fire because it is flammable so the new hypothesis, if the contaminated water is filtered through filter paper and pushed down by gravel, then the water will be separated from the oil, was formed.

1. Insert filter paper to fit funnel at the neck of the Erlenmeyer flask. 2. Pour the contaminated water into the funnel and into flask. 3. Take gravel and push down mixture into the flask. **Data/Observations:** the top is a slick oil and the bottom is a dark, dirty water that smells of garlic and sulfur. || About 5 mL || The only liquid inside of the container is an oily golden liquid that appears to be much cleaner than the first sample, but it still smells of oil remnants. ||
 * Procedure:**
 * Procedure ||  Approx.   Time  ||  Initial   volume (mL)  ||  Observations  before procedure ||  Final volume (mL)  ||  Observations  after procedure ||
 * Start || 13 min. || 15 mL || There are two layers -


 * Calculations** :


 * Percent yield = ( Initial volume / Final volume ) x 100
 * = 5/15 x 100
 * = Approximately 33.3%


 * Discussion** : By the beginning of the experiment, it was expected that the oil would be removed entirely from the water. However, only the dirt was filtered out of the water. The expectations of the experiment did not lead to success however it brought a clearer idea of how the next trial has to be performed. This experiment turned out to be the right thing to do even it if it failed because it only eliminated this hypothesis so that a new hypothesis could be formed again. The procedures did not take into account that gravel would push both water //and// the oil into the Erlenmeyer flask. Because of this the outcome was still a mixture of oil and water but only without the dirt.


 * Conclusion** : According to the hypothesis, the expectation of filtering the foul water was eliminating the oil from the water. However, the experiment that was performed only filtered out the dirt from the water. By the end of the experiment there were still two layers in the mixture. It would have been more efficient if the experiment involved sand because it may somehow absorb the oil leaving only the water but that plan was not thought of soon enough. The experiment did not meet the initial prediction that was made but this failure was easy to learn from. The failure of this experiment opened up a clearer understanding of how important it is to create a hypothesis that will logically lead to success.

//There is still a layer of oil.//
 * Result:**

Samantha Atamian, Chelsea Brennan, Aubrey Postolakis, Megan Ruiz  CP Chemistry   Period 6   September 28, 2010 __ Foul Water Trial 2 __ **Introduction**: For trial 2 of the activity, the goal was to successfully separate the oil from the water. Since this goal was the same as trial 1, there had to a different method of filtering out the oil from the water. The sample of water shows two layers, oil and water. The odor coming form the water smells of garlic, which means the water also contains sulfur. Also, there is evidently dirt and other contaminates floating around in the water. Obviously a new hypothesis was formed which states, if the water is poured in a funnel covered in filter paper, and filled with sand and gravel, then the oil will separate from the water. Because of the failure of trial 1, the factors of sand and gravel were added into the new experiment in hopes of trapping the oil thus separating the water and the oil.

**Procedure**:
 * 1) Insert filter paper into the funnel to fit the neck of the Erlenmeyer flask.
 * 2) Pour sand and gravel into the funnel and filter paper.
 * 3) Pour mixture into the funnel and filter paper.
 * 4) Collect water at the bottom of the Erlenmeyer flask.

**Data/Observations:** before procedure ||  Final volume (mL)  ||  Observations after procedure || - Contaminates floating around. - Brown - Odor: garlic. || 70mL || - 1 layer - No contaminates floating around. - Yellow - Odor: //still// garlic. ||
 * Procedure ||  Approx. Time  ||  Initial volume (mL)  ||  Observations
 * Mixture poured into funnel and filter paper. || 10 minutes || 90 mL || - 2 layers

**Calculations:**
 * Percent yield = ( Initial volume / Final volume ) x 100
 * = 70/90 x 100
 * = 77.8%
 * 20 mL of impurity, including dirt and oil, was removed.

**Discussion**: From trial 1, it was easier to base the new hypothesis for trial 2. Because the last experiment did not successfully separate the mixture of oil and water, it became important to find a factor to add in the experiment that //would// separate the two substances. The sand and gravel became the new components that led to the outcome of the separation of the oil and water. It was inferred that the sand and gravel would trap the oil because of oil’s larger viscosity than water. The oil and contaminates of dirt were removed from the water and trapped in the sand in gravel of the funnel. The time it took and the amount of water that was obtained may turn into a challenging factor when trying to entirely purify water.

**Conclusion**: The final outcome of the water proved the hypothesis to be true. The procedure of the lab did successfully separate the oil from the water. However, it took 10 minutes to obtain only 70 mL of oil and contaminated-free water after starting with 90 mL of water. Also, this experiment did not focus on getting rid of the odor or tinted color of the water either. This poses a new challenge that must be thought of in trial 3. Regardless, the success that the water and oil has been separated brings the answer of purifying the water completely much closer.

//There is no longer a prominent layer of oil – most of the oil has been separated from the water.//
 * Result:**

Samantha Atamian, Chelsea Brennan, Aubrey Postolakis, Megan Ruiz CP Chemistry Period 6 September 29, 2010 __Foul Water Trial 3__
 * Introduction** : Since most of the oil has been separated from the water, the main goal for the sample of water for trial 3 was to eliminate the odor and the yellow color. The odor coming from the water smells of garlic, which concludes that the water contains sulfur. In order to get rid of the smell the hypothesis, if the water is poured into a funnel of filter paper and charcoal then the odor and the color will be gone, was formed. This hypothesis was formed because the former 2 trials did not get rid of the smell or color by using sand or gravel. Charcoal seemed to be the last option.


 * Procedure** :
 * 1) Insert filter paper in the funnel.
 * 2) Place the funnel on a ring clamp attached to the ring stand.
 * 3) Pour the charcoal into the sample of water.
 * 4) Stir the mixture.
 * 5) Pour the water into the filter paper.
 * 6) Collect the clear water at the bottom of the Erlenmeyer flask.


 * Data/Observations** :

before procedure ||  Final volume (mL)  ||  Observations after procedure || - Smells of garlic meaning it contains sulfer. || 40mL || - Color is clear. - No odor. ||
 * Procedure ||  Approx. Time  ||  Initial volume (mL)  ||  Observations
 * Pour water into filter paper and collect clear water at the bottom of the Erlenmeyer flask. || 4 minutes || 70 mL || - Color has a yellow tint.

 = 40/70 x 100  = 57.1%
 * Calculations** :
 * Percent yield = ( Initial volume / Final volume ) x 100
 * 30 mL of impurity, sulfur and the color, was removed.

**Discussion** : During the procedure, the expectation of the experiment was that the yellow and garlic smelling water would turn clear and have no odor. The experiment turned out to be a success when the water collected from the Erlenmeyer flask was clear. The charcoal was able to absorb the substance that gave the sample of water a bad smell and a cloudy color. The once heterogeneous substance is slowly turning into a homogeneous substance. The oil is already separated from the water, now so is the sulfur.

**Conclusion** : The now clear water poses a challenge of purifying the substance completely. Because there may have been imperfections during the experiments and trials, another trial has to be done to make sure that the water is completely safe enough to drink. However, trial 3 turned out to meet the exact expectations of the hypothesis.

//The water is now clear.//
 * Result:**

Samantha Atamian, Chelsea Brennan, Aubrey Postolakis, Megan Ruiz CP Chemistry Period 6 October 1, 2010 __Foul Water Trial 4__
 * Introduction:** Now that the water was clear and odor free, fully filtering the water was the problem that was faced in trial 4. When the light bulb was attached to the battery and placed into the water, the blub lit up. That was evidence that salt was present in the water. It was concluded that salt water had leaked into the freshwater lake posing a new problem in filtering the water. The new hypothesis was formed; if the water is boiled, then the evaporated and condensed water will be salt free. In order to do this, the sketch was drawn that an Erlenmeyer flask would stand over a Bunsen burner while rubber tubing is attached to the flask. The rubber tubing would have two tubes while on the inside tube it would be hallow and the outside tube would collect cold water from the lake that would help the condensed water down the tube and into the other flask on the other side of the tubing.

1. Place a round bottom flask over a Bunsen burner. 2. Connect rubber tubing going downwards to the flask over the Bunsen burner and to a flask at the other end of the tubing. 3. Pour in contaminated water into the flask over the Bunsen burner. 4. Let water boil. 5. Wait and record results from the water collected in the second flask.
 * Procedure:**


 * Data/Observations**

before procedure ||  Final volume (mL)  ||  Observations after procedure || - No odor. - Contains salt. || 62mL || - Color is clear. - No odor. - Does not contain salt. ||
 * Procedure ||  Approx. Time  ||  Initial volume (mL)  ||  Observations
 * Distillation – Vaporizing the water so that it would condense and evaporate. The remaining water was collected salt free. || About 30 minutes. || 64 mL || - Color is clear.

 = 62/64 x 100  = Approximately 96.9%
 * Calculations** :
 * Percent yield = ( Initial volume / Final volume ) x 100
 * 2mL of salt was removed from the original substance of water.

**Discussion:** Again, the original hypothesis and expectations for this trial turned out to be a success. The experiment that was done was a simple way of viewing distillation. Because the water was vaporized, condensed, and then evaporated, the remaining liquid was collected and it turned out to be salt free. This was the process of distillation done in a lab. Most of the impurities were removed from the water already, and in trial 4 the salt was removed. This met the exact expectations of the hypothesis.

**Conclusion:** The once heterogeneous substance has finally tuned out to be homogenous with all of its similar elements the same. The level of success was very high in this trial because the past trials had greatly helped. Because of the success in the past experiments it became easy to produce a new hypothesis that would lead to clean water. From performing this activity it became clear that the more accurate the hypothesis was, the more successful the results would be.

// Processing result of Trial 4. //