Introduction
It’s that time of the year DP2s – time to finish off your CAS Project as you slowly inch towards the dreaded M2024 session. With the volume of work we’ve had piled up – internal assessments, TOK essays, assignments and exam revision – sneaking in time for a CAS project seemed impossible. But with a bit of creativity, and loads of resourcefulness, ideas come your way.
I take quite a bit of pride in my proficiency in scientific literacy – whether that be obscure experiments or mastering the core content demanded by the IB program. I take pride because I utterly love the discipline: the excitement, the novelty and sheer mystery behind each puzzle which we call a theory. Coupled with my involvement in the Cultural Exchange Program – my own service group where we aim to improve English proficiency of underprivileged children around Colombo – I could already see a viable project developing.
Now a boring old lecture on the reactivity series isn’t what I was thinking of – these children probably receive an excessive amount of such teaching. I wanted to share what is unique about the OSC experience – a copious amount of intricate fiddling, messing and playing around with scientific toys in our day to day classes (for the less imaginative, experiential learning is the proper term used). It slotted perfectly to my service-oriented goals – these children, some of which have proven their academic abilities to be far more advanced than what I possessed at their age, don’t get the opportunity to see science in action. No experiments, no field trips, no amusement.
Science, for the majority of children including in better-off schools, is just a painted ship upon a painted ocean. It’s a textbook full of stuff needed to pass that exam. They’re taught lifeless science – which cultivates an equally lifeless disposition towards the discipline. And it’s not their fault that they don’t have an equal opportunity to experience science – they deserve to.
Therefore, it was settled. I would demonstrate a few sensory experiments that cover a wide range of scientific knowledge to these underprivileged group of children that arrive at school for service – something that they can brag about and remember fondly. After employing the necessary permissions from Mrs. Lockwood to steal her cohort of children to teach, and running by due safety protocols needed to be adhered with for each experiment with Mr. Leblanc, the following practicals were selected.
Metal ion flame tests
The most dangerous, yet the most visual experiment of all. The metal ion flame tests involve exposing salts of different metal ions to a roaring flame which colors the flame different colors depending on the metal present in the salt. It was very simple to set up, with 6 different Bunsen burners stationed around the lab, a few nichrome wires (to collect the salt and hold it against the flame) and hydrochloric acid to clean the wires before each use.
Safety was my biggest concern. Apart from wearing safety glasses and asking them to stand at least a foot away from the flame, I was constantly reminding the kids to maintain their distance – and nudging those ambitious few away from the warmth of the flame. After all, it was a bunch of 12-14 year old children, they wanted to play around – but to my surprise, all of them were very understanding.
The following salts were used, producing a corresponding unique flame color:
Strontium Chloride (deep red flame)
Lithium Chloride (pale red flame)
Copper (II) Chloride (blue-green flame)
Potassium Chloride (lilac flame)
Iron (II) Chloride (yellow flame)
Calcium Chloride (orange flame)
Voltaic Cell Activity
For this practical, I followed a demonstration detailed by the Royal Society of Chemistry to make a small battery in a petri dish. This practical required dilute solutions of a copper and zinc salt (I used copper sulfate and zinc sulfate), small pieces of the pure metals themselves, a dilute solution of sodium nitrate, filter paper, and a few petri dishes.
After dividing the group of children into 3 groups, and giving each group their own set of materials to carry out the practical (one petri dish, a piece of filter paper, a pair of scissors, a piece of zinc and copper metal, a 5V analogue voltmeter and solutions of CuSO4, ZnSO4 and NaNO3), I demonstrated the practical and asked them to follow along with their equipment. It’s quite simple – you cut your filter paper into a shape of a cross and place it in the petri dish, and place the piece of zinc on one end of the cross, and the piece of copper on the other end. Afterwards you put a few drops of CuSO4 on the copper metal, and a few drops of ZnSO4 on the zinc, and a few drops of NaNO3 in the middle – then connect the ends of the voltmeter to each metal piece and voila! You have a battery!
The faces of exclamation on their faces were quite precious. They’ve made their first battery, and they were visibly proud of it!
Esterification: Apple fragrance
The most tricky experiment. This experiment was adapted from one of Mr. Leblanc’s laboratory handbooks for AP Chemistry. It involves heating a mixture of butan-1-ol, galactic ethanoic acid and concentrated sulfuric acid (corrosive) under reflux for around an hour to produce the ester, butyl ethanoate – which smells distinctly of apple.
Due to the corrosive nature of all the reactants used, I carried out the experiment myself, whilst wearing proper safety gear, and explained the chemistry of the experiment as it progressed to these kids in sinhalese. I started the experiment and left it to react, and then proceeded to perform the flame tests and voltaic cell activities before coming back and finishing off our session by taking a quick whiff at the final reaction mixture after an hour had elapsed – and yes, it smelled of apple!
Even though I could explain the chemistry, most of the children looked at me as some sort of witch. I created the smell of an apple, without an apple. That is the beauty of science – that look of perplexion yet awe on their faces. It was all the reward I needed.
