An afternoon lesson

I could remember what time it was - 12.35pm. This was when the picture above was taken - on the 29th of June, 2015 at Federal Government Girls College, Owerri, Nigeria. These students had come in for their practical chemistry lesson. There were about twenty of them. They had come in, excited and full of expectations for the class. They moved directly to their already assigned tables. I had previously grouped them, so they settled down quietly with no fuss. They were going to carry out Titration, an important aspect of practical chemistry. Here, the volume of a titrant(usually an acid) of very low molar concentration that reacted with an analyte (usually a base) of very low molar concentration was determined. However, I would not go into details of what the whole exercise entailed. I would like to mention however, that adequate preparations had been made previously, in order to achieve the desired outcomes of the lesson. Every required item had been brought out and carefully placed on the tables. These items included; burettes, pipettes, Erlenmeyer flasks (conical flasks), reagents(titrant and analyte), indicators and so on. Suffice to say that the students arrived with the expectation of successfully carrying out a simple titration. I was full of high expectations for them as well, because of their organizational skills observed in similar situations. As I watched them settle down, I knew that nothing could possibly go wrong. I had made sure of this, by consulting the lab attendants and utilities department, the day before, about the provision of water and electricity. It would help greatly, to conduct the practical class under a conducive atmosphere. I began with a quick demonstration, as a reminder of the procedure required to carry out a simple titration. I had carried out the same task thrice before and explained the rules guiding this activity. The girls were all attentive as I carried out the demonstration and asked some questions. I was happy to provide answers to them as I was encouraged by their enthusiasm. I recall that one of them had commented offhand, as I carried out the demonstration that I had perhaps swallowed some of the analyte(base), while sucking it up from a beaker, using the pipette. But this did not bother me in the least, as I was more interested in their ablity to carry out the activity successfully. 'Now, is the time to show me what you can do,' I had said jocularly. This was a clear signal to begin the activity in earnest. I also reminded them about the do's and don'ts governing the experiment and I was satisfied they understood it, based on the general replies given. They had all of the rules guiding the Titration experiment, pat. I was impressed at the zeal shown by these girls as they carried out the practical in earnest, in their various groups. There was effective collaboration - which was great. I moved around and watched them as they became engrossed with this activity. I made a few suggestions and assisted a few as I watched and supervised. There were some incidents though- but they were not serious. There were a few of them that got the analyte into their mouths and had to spit out in the in the lab sinks. But no worries. These were bound to happen anyway. Moreover there was no cause for alarm, as the molar concentration of the analyte was insignificant to be harmful. I observed from some of the recordings, that the values of the titrant obtained by the different groups, varied significantly. I attributed this to some errors made while carrying out the experiment. I raised no brows at this, as it was their first time of carrying out this experiment. I was satisfied that they understood the procedure. I was also confident that the readings would be more accurate in subsequent practical lessons, based on my teaching experience. And it happened exactly as I thought. So, back to their first trial....The students were specially careful as they used the instruments provided. I looked at the time and realized that the lesson was almost over. The students realized this too and were actually eager to begin clearing up. They helped to wash the instruments used and that was really great. The lab attendant also assisted to tidy up the clutter. All this took about five minutes as everyone was involved. The bell was rung some minutes later, formally signaling the end of class. The students moved out in just the same way they came in....chatting in hushed tones but now, a little bit higher.

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