Sunday, 19 June 2011

3.4 recall the products of the complete and incomplete combustion of alkanes

1.        Saturated hydrocarbons are called alkanes
2.         Small chain alkanes are used as fuels.
3.       The reaction is called combustion.
4.       The word equation for  this chemical reaction is :
fuel  + oxygen → CO2 + water + ENERGY (heat, light, sound)
5.       If there is insufficient oxygen then the word equation is:
fuel  + Insufficient oxygen → Carbon Monoxide + water + ENERGY (heat, light, sound)
6.       The problem with this reaction is that Carbon Dioxide is produced this gas is a poisonous to the human body (see objective 5.11)
7.       Where can you find incomplete combustion?  Car Engines
8.       What is used to reduce the harmful products from incomplete combustion? Filters
9.       During incomplete combustion a smoky flame is often seen, explain this observation, this is showing the formation of Carbon Monoxide in the form of soot or a smoky flame. 
10.   Describe the two chemical tests for water  ph= 7 and Blue anhydrous cobalt chloride turns pink when there is addition of water to it

Read more: http://wiki.answers.com/Q/What_is_the_chemical_test_for_water#ixzz1PjWQbOFR
11.   Describe the chemical test for carbon dioxide gas Lime water turns milky
12.   Describe a physical test for water boiling point =100 Celsius