Introduction: The theme we had for our Group 4 project, in collaboration with Oporto School, was Bathroom Science. Our groups were chosen completely at random. Group B consisted of two biologists and two physicists. Our group found it hard to produce ideas as we the majority of the ideas we came up with were Chemistry orientated. However, we found an investigation that was relevant to our every day life in Rome. The excessive calcium levels in the water of Rome.
This is our aim:
To investigate calcium level in water sources around Rome and the implications this may have on internal health, hair and skin.
This idea seemed highly interesting because of how applicable it is to us in our lives. It is known that the calcium levels are very high in Rome so we wrote up an experiment looking at different water sources around Rome, mostly around our school. Also, the damage that excessive calcium may do to our health raised an interesting point of investigation.
DAY 1
We simply measured out 15 cm3 of water. We measured the original mass of the evaporating dish on a balance. We then poured the 15 cm3 of water into the evaporating dish and weighed the mass of the two things combined. By doing this we calculated the mass of the water. We then evaporated the water and waited for it to cool down. We then weighed the evaporating dish. We did this for all 4 sources of water and found a white residue in the evaporating dishes. Source A, which was from the normal tap water, had the most residue in it. Unfortunately, the mass appeared to be the same before and after the experiment. Moreover, there was not enough residue to make flame tests to test for calcium thus failing our experiment. However, we decided to try the experiment again, but this time we used a more sensitive balance.
B: Starhotels, Bath foam tea leaves
C: Doccia gel
D: Marsiglia + Olivia d’olivia: Sapone Liquido
We started the day, by gathering our equipment and gathering 4 different water sources from near school. The sources were
- Fizzy bottled water
- Tap water from the science lab
- Fountain water from across the street
- School drinking fountains
Our apparatus consisted of
- A Bunsen Burner
- Tripod
- Gauze mat
- 4 evaporating dishes
- Balance
- Measuring cylinder
We simply measured out 15 cm3 of water. We measured the original mass of the evaporating dish on a balance. We then poured the 15 cm3 of water into the evaporating dish and weighed the mass of the two things combined. By doing this we calculated the mass of the water. We then evaporated the water and waited for it to cool down. We then weighed the evaporating dish. We did this for all 4 sources of water and found a white residue in the evaporating dishes. Source A, which was from the normal tap water, had the most residue in it. Unfortunately, the mass appeared to be the same before and after the experiment. Moreover, there was not enough residue to make flame tests to test for calcium thus failing our experiment. However, we decided to try the experiment again, but this time we used a more sensitive balance.
This time, to try and increase the mass difference, we used 4 different types of soap and collected water used after washing Romeo's hands.
We repeated the same experiment as above using only 10 cm3, but with a more sensitive scale. Again we obtained strange results. In two of our evaporating dishes the mass was actually lighter than before. This could've possibly been because of the dishes not be entirely dry before the experiment or other chemicals already being in the dishes. Sources C and D did work and the changes were minimal (differences in second or third decimal places). Again, the residue was too little to measure. Furthermore, the mix of chemicals could've produced very unclear results in a flame test.
We repeated the same experiment as above using only 10 cm3, but with a more sensitive scale. Again we obtained strange results. In two of our evaporating dishes the mass was actually lighter than before. This could've possibly been because of the dishes not be entirely dry before the experiment or other chemicals already being in the dishes. Sources C and D did work and the changes were minimal (differences in second or third decimal places). Again, the residue was too little to measure. Furthermore, the mix of chemicals could've produced very unclear results in a flame test.
Day 2
With the days previous failures, we decided to step away from water composition experimentation and take on an entirely new experiment. Our aim this time was:
To Investigate the Optimum Conditions for Foam to be Produced
We decided to investigate the optimum temperature, velocity and soap type.
Temperature:
We used a volume of 2 ml3 of soap and a volume of 175 ml3 of water. Rather than 4 different sources of water we used for different brands of Soap. Which were
A: Bagno crema rilassante
B: Starhotels, Bath foam tea leaves
C: Doccia gel
D: Marsiglia + Olivia d’olivia: Sapone Liquido
We heated water to 4 different temperatures: 20˚c, 50˚c, 75˚c and 100˚c and placed the water into a measuring cylinder where the soap was. We measured the volume of the foam that was produced. We repeated this for all 4 soaps and all 4 temperatures. The hotter temperatures we used clamps and heat proof gloves to left them. We found that it seemed that 75˚c was the optimum temperatures, but this did not necessarily apply to all soaps. This could depend on the brand of the soap or the velocity of the water hitting the soap. Though the two measuring cylinders used have the same volume, they did not have the same shape which meant that this may have affected the results. We thought that a higher velocity would also mean more movement and therefore produce more bubbles.
Velocity:
We used a tank to collect the water and measured out its volume. The soap was placed in the tank (2 ml^3 of it) and we placed rubber tubing on the tap as a control (this meant the water would not splash uncontrollably). We measured the time taken for the water to fill the volume of the tank and used this to measure the speed. We tested with all 4 soaps with 3 different velocities (approximated because we could not accurately control the speed of the water) and discovered that foam produced relied mostly on the water's velocity. We also discovered that if the water hit the soap from above that it produced more foam than if we simply filled the tank. This means that the force of the water hitting the soap was a vital factor to the majority of foam produced.
Overall, our failures in our experiments only aided us in creating more accurate and controlled experiments, thus finally drawing us to our final investigation resulting in a discovery that brought us through chemistry and physic related areas that the majority of our group had not ventured in since GCSE years.
