Objective

      To find out how the solution of substances found in cigarettes and water affects the growth and mortality of bacteria. To investigate the amount of certain substances found in a cigarette.

Daily diary

24/09/14: Today, we talked about our experiment and tried to decide a specific theme. We wanted to do a culture of bacteria and thought that proving their lethality in the substances found in cigarettes would be a good idea.

01/10/14: We started out background information. The most important information we needed to search was the different cigarette's substances. It is also important to understand of bacteria and their life spans and reproduction.

08/10/14: We searched the percentage of the substances in a cigarette and completed all the information of the previous day.

22/10/14: Last day, we started the method and materials which are necessary for the experiment. After talking to Mr. King we decided to change our experiment due to the fact that it wasn’t possible to obtain some of the materials. Now, we are going to make a solution with the cigarette and water, and prove the lethality of it. The benefit of doing it this way is that we can search for the amount of certain substances in the solution with a spectrometer.

Due to the change of experiment we had to add more information about solutions, and about the electronic stirrer (which we would use to make the solution).

29/10/14: We had finished the method and the materials and changed the investigation question and objective. And, from now until the dateline we are going to improve everything that is in our hands.

05/10/14: Today, we searched for the solubility in water of the most abundant substances in the cigarettes at 20-25ºC. We did this to know what substances would be dissolved the most, and which of them should be out target with the spectrometer.

12/11/14: Today is the last day, so we needed to pass all the information and work we have done, from the blog to a word document.

14/01/15: Today we started working on the experiment. To begin we measured 5g of tobacco. We mashed the tobacco with a mortar and added 200mL of distilled water. Then we shook the mixture, and used the magnetic stirrer. We are waiting until the solution is complete homogeneous.   

28/01/15: Today we started to do another solution of tobacco following the same steps, and we also started to filter the other one. Next, we modified some data of the report from the experiment. We have asked our teachers for help with the elaboration of bacteria culture. We left the last solution on the electronic stirrer to facilitate the solution of tobacco with water.  

4/02/15: We have filtered the last solution and we started to design and write the method to create the bacteria culture. We are also collecting photos to show the process and for the next week we are going to start with the bacteria culture. 

11/02/15: Around this week we have prepared the bacteria culture following the necessary steps, then we left it at the refrigerator to maintain the product. We also collected more photos and now we are waiting for the bacteria, which are not available right now. Then we are going to prepare different solutions and then we are going to use the spectrometer to measure the growth of bacteria.

18/02/15: We mixed the water with tobacco, separated into 8 different recipients, in which is going to progresively vary the amounts of water and tobacco, starting with a solution of only water and ending with a measuring cylinder with just tobacco. We will add bacteria this week, because today the bacteria are not available, and if possible this week we also will make a new culture of the new bacteria.

25/02/15: Today half of the group were working with the report and data of the experiment, and the other half had been doing the final part of the experiment and collecting the results using the spectrometer.

11/02/15: Around this week we have prepared the bacteria culture following the necessary steps, then we left it at the refrigerator to maintain the product. We also collected more photos and now we are waiting for the bacteria, which are not available right now. Then we are going to prepare different solutions and then we are going to use the spectrometer to measure the growth of bacteria.

18/02/15: We mixed the water with tobacco, separated into 8 different recipients, in which is going to progressively vary the amounts of water and tobacco, starting with a solution of only water and ending with a measuring cylinder with just tobacco. We will add bacteria this week, because today the bacteria are not available, and if possible this week we also will make a new culture of the new bacteria.

25/02/15: Today half of the group were working with the report and data of the experiment, and the other half had been doing the final part of the experiment and collecting the results using the spectrometer.

Timetable