This is a blog created by Ms Luminati (science teacher), Ms Mathis (English teacher) and Ms Burguière (science teacher) for the students of lycée expérimental André Malraux (Biarritz, France) who are learning science in English. They want to show that science is fun, interesting and easy particularly when it is done in English!
This year we hope to work again with some fine European partners.
Let us all have fun together!
Thursday, 13 April 2017
Our project is about Orange Juice.
We have make experiment with this orange juice.
Our leading question is "Why you have to drink quickly an orange juice?"
The goal of this titrationwith EDTA is to detect the presence of ion calcium in tapwater. To prove this presence of this ion you must to put on a becker tapwater with indicator and over this becker you put on the buret a solution of EDTA. EDTA react with the ion calcium and the indicator. With the volume equivalent you can calcul the concentration of ion calcium in the tap water.
Andony Gatinaud Barberteguy, Vincent Mirailh and Thibaut Latapy
are going to talk about an experiment of our project. This experiment
consists in extract the oil from the sunflower's seeds.
have mix 30g of sunflower's seeds with 10mL of cyclohexane. The
cyclohexane has the role of solvent in order to extract the linoleic
acid contained on the seeds. At the end of this experiment, it stays
only cyclohexane and linoleic acid.
We have carried out experiment about pH of the water :
Protocol : Pour 1 mL of each water in test tubes, then measure the pH with this different techniques : color indicator like Cresol Red or Tymol blue, pH paper and pH meter. Test tubes contain : 1 : Sea water 2 : Soapy water 3 : Hepar water 4 : Acetic acid 5 : Tap water 6 : Distilled water
First we have measured the pH of different water with the Cresol red
Then we have measured with the Tymol blue
After that we have used pH paper
And at the end we carried out experiment with the pH meter
The results with pH meter are more precise than others.
To measure the hardness of sea water we : - Fill a burette with 0,01 M EDTA. - Add 10 mL of sea water with a 10 mL pipette and a bulb, to a 250mL erlenmeyer flask, along with 20mL of the ammoniac buffer and 6-8 drops of eriochrome Black T indicator. - Swirl -Put a burette above the flask, filling it with EDTA and turn the stopcock to add solution drop by drop. When it's blue, close the stopcock. -Calculate the equivalent mL of calcium carbonate per L.
To know the pH of different water samples we use the "cresol red" , it's a simple experiment : we pour different water for example sea water, soapy water, hepar water, acetic acid, tap water, distilles water.
- We have to remove around 5mL of a water sample to a test tube
- Add some drop of cresol red in the test tubes and compare with the pH color indicator.
- Do the same experiment with the thymol blue.
Pour 5mL of distilled water into each of the empty test tubes ( 2 ).
Add 5g of epsom salts ( magnesium sulfate ) to one of the test tubes.
Stopper or cap and shake the test tube until the epsom salts dissolve.
Add a drop of liquid dish detergent to both test tubes.
Seal the test tubes with their caps or stoppers.
Shake both test tubes