Chemistry practicals (1 Viewer)

[lyounamu]

Can anyone post their chemistry practicals for Energy Module and the calorimeter experiment from water module? (method, aim, discussion etc)

Thanks~~~

 

[bubblesss]

the pracs we did for the energy module were -
1) model the formation of single, double and triple bonds in simple carbon compounds using molecular model kits.
2)use the process of fractional distillation to separate the components of a mixture such as ethanol and water.
3) did an experiment to show if the reaction is endothermic or exothermic.
4) to prove that the rate of the reaction is affected by factors such as temperature. concentration, catalysts and size of the particles.
5) molar heat solution of substances such as ammonia and sodium hydroxide.

thats about all we did.:uhhuh:

do u need the pracs with method aim etc???

 

[lyounamu]

the pracs we did for the energy module were -
1) model the formation of single, double and triple bonds in simple carbon compounds using molecular model kits.
2)use the process of fractional distillation to separate the components of a mixture such as ethanol and water.
3) did an experiment to show if the reaction is endothermic or exothermic.
4) to prove that the rate of the reaction is affected by factors such as temperature. concentration, catalysts and size of the particles.
5) molar heat solution of substances such as ammonia and sodium hydroxide.

thats about all we did.:uhhuh:

do u need the pracs with method aim etc???

Yeah, that will be great.

 

[bubblesss]

just realised my prac book is with my teacher but i'll type up expt 4 because it is really important and we got it in our prac test and i remember it well.

aim: to prove that the rate of a reaction is affected by factors such as temperature, concentration. size of reacting particles and catalysts.

METHOD:
1)temperature: take 3 small beakers of same size and pour 5o mL of Hcl 1 mol/L
into each beaker. each beaker is placed in a water bath at 0, 25 and 50 degrees respectively. three magnesium ribbons of the same size are dropped into each beaker at the same time. the time taken for each reaction to complete is noted.

2) concentration: 4 test tubes with varying concentrations of Hcl such as 0.5 , 1,1.5 and 2 mol/L are taken. 4 pieces of magnesium of the same size are taken and placed in each test tube at the same time. the time is noted.

3) size of particles: take 2 tablets of (not sure of the name) and crush one of them into fine powder. take two test tubeswith 1 mol/l Hcl and place the tablet and the powder into the 2 test tubes at the same time. record the time taken for completion of reaction.

4)catalyst: take a beaker and pour 30 ml of hydrogen peroxide and let it decompose. observe the rate of the reaction. after a while add a bit of manganese dioxide(black powder) and observe how the reaction proceeds.

 

[bubblesss]

discussion:

1) temp: it was found that the reaction taking place at 50 degrees bubbled vigorously and was the first to finish.

2) concentration: it was found that the reaction taking place in the presence of the highest concentration (2 mol/L) fizzed and was the fastest.

3) size of particles: the tablet took a way longer time than the powder to complete. the powder bubbled and fizzed and the reaction was complete in abiut 1 and half minutes.

4) catalyst: the decomposition of hydrogen peroxide was extremely slow. however after adding manganese dioxide the reaction took place at an enormous speed.

note: the reaction is said to be complete when the fizzing, bubbling and decomposition of all gases have stopped.
the reliability can be increased by repeating the experiment several times.

RESULTS:
1) higher the temperature, faster the rate of reaction
2) higher the concentration. faster the rate of reaction
3)smaller the particle i.e larger the surface area for chemicals to come in contact and react hence faster the reaction
4) manganese dioxide acted as a catalyst and sped up the reaction even though it didn't take place in the reaction itself. thus the use of catalysts increases the rate of reaction.

 

[lyounamu]

discussion:

1) temp: it was found that the reaction taking place at 50 degrees bubbled vigorously and was the first to finish.

2) concentration: it was found that the reaction taking place in the presence of the highest concentration (2 mol/L) fizzed and was the fastest.

3) size of particles: the tablet took a way longer time than the powder to complete. the powder bubbled and fizzed and the reaction was complete in abiut 1 and half minutes.

4) catalyst: the decomposition of hydrogen peroxide was extremely slow. however after adding manganese dioxide the reaction took place at an enormous speed.

note: the reaction is said to be complete when the fizzing, bubbling and decomposition of all gases have stopped.
the reliability can be increased by repeating the experiment several times.

RESULTS:
1) higher the temperature, faster the rate of reaction
2) higher the concentration. faster the rate of reaction
3)smaller the particle i.e larger the surface area for chemicals to come in contact and react hence faster the reaction
4) manganese dioxide acted as a catalyst and sped up the reaction even though it didn't take place in the reaction itself. thus the use of catalysts increases the rate of reaction.

That's really awesome. Thanks~~

I didn't get to do the experiments due to absence. It's great that I have got something.

TO others: if you have any other experiments...please post them up~~~ thanks~

 

[12o9]

It's pretty bad =/ but i guess it's better than nothing.