A2 and AS Chemistry OCR Practical ExamWatch
- Plan an experiment that would enable you to find out weather or not the rate of decomposition depends on the surface area of the solid catalyst used.
- Plan another experiment by which you could determine the order of reaction for this decomposition with respect to hydrogen peroxide.
Any1 any suggestions for stuff to include?
u no for the second part, bout the order of reaction we can keep the catalyst surface area constant and dilute the solution. got ne ideas on how to dilute the thing to weaker concentrations??
the stuff is apparently 10 volume which means...
1cm3 of hydrogen peroxide will give 10cm3 of oxygen gas under decompostion.
so wed use 10cm3 to get 100cm3 of gas as 10cm3 wud happen 2 fast.
so if the solution was diluted to 5volume 1cm3 wud give 5cm3 of gas...
but each time we wana collect 100cm3 to keep this variable constant, so wud i add 10cm3 of water to the original 10 volume solution, making it 5volume?? then this 20cm3 of 5volume solution wud give 100cm3 of gas???
am i on the right lines?? any ideas wud be greatly appreciated??
Can anyone assist me with my method? As we're testing unknown solutions, I proposed to test a small sample of each of the 5 solutions (in a test-tube) with each test I intend to propose, e.g. add AgNO3 to each tube, shake, leave to stand and make obs; add dilute NH3 to those which reveal a white and cream ppte, shake, and leave to stand. AgCl will be sol in dil. NH3, whereas AgBr will only dissolve in conc NH3. Am I on the right lines?
The remaining tubes that didn't show +ve result to the halide ions test, will be tested for the presence of Ca(OH)2, HNO3 & CH3COOH. Again, if the brown ring test is confirmed by one of the 3 solns, then a credible inference can be made, etc.
hot reflux with conc. H2SO4
ethanoic acid + ethanol ----------------------------------> ester+ water
the ester is Ethy Ethanoate
you can smell this ester distinctively!!!
thus a positive test!!!!
Check out the above site. The questions are answered by teachers.
PLZ CAN COMEONE HELP ME ON THE TITRATION PART OF THE CHEM PLANNING. I HAVENT GOT A CLUE ON IT
THANX [/i dont have a clue either]