2010-03-31

SPM Corner - Alkenes


Isomerism


To view a list of isomers for all alkanes, please click here.

Compare Hexane and Hexene

Recently my students just carried out experiments to compare hexane(C6H14) and (C6H14) in terms of sootiness of flame during combustion. Filter papers are used to collect soot formed during the experiments.



It is obvious from the filter papers, hex-1-ene produces more soot than hexane during combustion. It is due to percentage of carbon content.   Though both hex-1-ene and hexane have 6 carbon atoms per molecule, but hex-1-ene has higher percentage of carbon content than hexane.

2010-03-12

Paper 3 SPM 2005 - Planning an Experiment


In paper 3 Chemistry SPM, a student is asked to plan an experiment based on the situation given. I have given this question to my students as an exercise. Most of the time, they would give me an wrong experiment plan. They planned experiment exactly the same as the experiment they carried out to investigate how the concentration of sodium thiosulphate affect its rate of reaction with sulphuric acid. 

Samples of answer please click here.

Aspirin


Aspirin is one example of analgesic which is normally used in treatment for headache and fever. However it is not suitable for kids as it can cause internal bleeding in the stomach.