Friday, 6 November 2015

Year 5 test materials

5L have been learning about useful properties of materials. They have been putting this knowledge into action in an experiment.

They tested materials to answer a number of questions.

How big is it?



Is it reflective?



Is it flexible? Is it strong?




Is it waterproof?


How hard is it?

Thursday, 5 November 2015

Year 6 get a little hot under the collar

6S were working with their Bunsen burners in the lab this morning
They heated a variety of substances and looked for physical and chemical changes 
 first was ice
ice, ice, baby 
to water and steam (physical change)
then paper 
which burned (definitely chemical)
Tin foil was interesting 
 it depended how hot it was and whether it could react with oxygen from the air
 when hot enough it was a chemical change
but at lower temperatures it only changed physically 
 
 
 
 
 
 
Finally wood and another definite chemical change 
Some very good observations were made today

7C learn all about the base

7C did a neutralisation expetriment today
They assembled their equipment and loaded the test tube with copper carbonate. 
 Sulphuric acid was added and a delivery tube was positioned to pass the gas evolved into limewater
 The lime water went cloudy showing that carbon dioxide was produced
 There was a blue solution produced
 after a few more pippettes of sulphuric acid much of the green copper carbonate had gone
The bits that were left were filtered out
 
The the filtrate was heated in an evaporating basin 
the solvent evaporated and the solute started to crystalise 
Soon blue crystals of copper sulphate were formed 
 Most of the hot solution was collected and left in a crystalising basin so large crystals can form.

Wednesday, 4 November 2015

Year 7 concentrate

Year 7 have been learning about concentration this week. They were presented with two acids and told they had different concentrations. They had to find out which acid, A or B, was the most concentrated.



They started by measuring 10ml of acid and adding universal indicator. 




They then slowly poured an alkali into their mixture and measured how much they had to add to turn the solution neutral. 




The acid that required the most alkali was the most concentrated. It meant that were more acid molecules to be neutralised. 


Its all about the Base

But these are chemical bases.
We are using copper carbonate to neutralise sulphuric acid.
The reaction produces carbon dioxide which we test with limewater
 The blue solution that is made has bits of unreacted green copper carbonate in it
 We have made lots of copper sulphate solution too
 We need to separate them by filtration
 the residue is the insoluble copper carbonate
 We heat the filtrate, copper sulphate solution, to evaporate the solvent, water, and leave us with the solute, copper sulphate crystals.