Good Practice – Carrying out a lab

Here is an idea I got from a colleague of mine recently for a novel way of getting your students to plan a lab investigation. It is a model that could be rolled back and used in a variety of labs and it is very straightforward to do. Essentially, you give the students a task (for example, testing for halides) and then give the students a framework in which they can plan their own personal investigation. For example, you give them ...

Oxidation States of Vanadium

Here is a great lab to use, whether it with regards to redox (topic 9) or transition metals (topic 13): Vanadium It deals with looking at the oxidation states of vanadium by reducing it with Zinc and the re-oxidising it with MnO4-. There is lots of good teaching to get over in this lab, from understanding redox and writing half equations to seeing that transition metals can have variable oxidation states through the colour of their ions. Please note, as with any lab outlined ...

Putting together a set of labs (practicals)

So, as a new teacher to IB you are slowly getting your head around teaching topic 1, plus you have started dipping into internal assessment. There are in fact a number of earlier postings in this blog relating to marking students lab work using the IA criteria - just search for IA or Design or DCP, etc. You are probably beginning to wonder how you are going to come up with sixty hours of lab work - this can seem a little ...

Rust remover lab

The molarities of the solutions are not given in this lab. This is intentional. As a teacher, it is your responsibility to thoroughly research the safety factors and respective molarities of reagents required for the completion of this lab.  Ethanedioic acid can be used to remove rust from steel. It also exists in two forms, anhydrous H2C2O4 and hydrated H2C2O4.2H2O. A redox titration can be used to deduce which form of ethanedioic acid is present in the rust remover. A standard solution ...

Alternative rates labs

Many of us are familiar with the ‘lost cross’ lab. Sodium thiosulfate and Hydrochloric acid are mixed, a yellow / white precipitate forms and the time it takes to obscure a cross is measured. In terms of an investigation, the lab works best for changing the concentration of the Sodium Thiosulfate but it can also be used to investigate the effect of temperature. Another good, less used rates lab is the ‘Iodine clock’. A solution of hydrogen peroxide and sulphuric acid are ...

Calculating a value for Absolute Zero

By Thursday, April 8, 2010 , , , , 0

This a nice, simple IA lab that is worth trying out. In a nutshell, the basic procedure is as follows: Fill a gas syringe with a single gas (Oxygen or Helium are good)   Cool the gas (at least five times), measuring the volume each time. Plot a graph of temperature (x-axis) vs volume (y -axis) and extrapolate This is just the basic outline for the method - if you need more details let me know. Not sure I would use it for Design ...

Possible Design Lab?

I am a big fan of New Scientist magazine - it is a very good read. At the end of the magazine there is a 'Last Word' column where readers can pose scientific questions so that other readers can offer answers or suggestions. The Last Word is so popular that they even produce books full of readers questions and answers. One such question caught my eye. It asked, why do cardboard fruit juice or milk containers bulge when they are empty ...

Making Metals

We have probably all carried out the reduction of Copper Oxide using Carbon at some time, maybe to show the reactivity series or maybe to talk about redox. I was wondering though if this could be used as a quantitative IA lab, 'Calculate the % Yield of Copper Produced From The Reduction of Copper Oxide With Carbon? (To assess DCP and CEv maybe?)   If one knows the mass of Copper Oxide, one should be able to calculate the theoretical mass of ...