CIE Oct/Nov 2018 session papers, marking schemes and other resources have been updated in our papers section.
Furthermore, we have also updated resources for Edexcel, OCR, IB, TOEFL, SAT, GMAT and more.
Click here for more information.
Good luck with your exams.
Discussion in 'Cambridge IGCSE' started by Utsm, May 23, 2013.
Guys now that we are done with chemistry share ur opinions on gt for A*
mark out of 200??
yes, out of 200
in the question about magnesium salts,was the volume of acid needed to neutralise noted or not?
it was noted
For the question that involves rusting. There was a question about what happens to the pH of the water when base is added to it, what was it's answer? And in what way can it help reduce the rusting which I wrote "It takes off dissolved oxygen so less chances of rusting". What did you guys write?
ionic equation what did you do guys in it variant 31
Ca^2+ + H2O + CO2
Guys yeah .. What did you write about the pH?
What about the solution of MgCl?
And how do we remove the indicator?
the answer for solution of magnesium chloride is as follows.
put 25cm^3 of HCl in a beaker and warm. Add powdered magnesium oxide by means of a spatula and stir by a glass rod. Stop the addition when no more magnesium oxide dissolves and then filter.The filtrate obtained is magnesium chloride solution.
I'm not sure but that's what i wrote.
The pH increases due to the addition of base.
Yes, as oxygen is removed, rusting cannot take place.
guys the question of the soluble salt that was made by titration,the question that asked how to remove the indicator.
in the question did he say that the volume of the acid needed to neutralise the base was NOTED or not?
yes the question said, that the volume of acid needed was noted!
and there was one ionic equation of displacment of a metal from a salt,what were the reactants again i remember it involved zinc
right silver nitrate i guess and zinc~
What abt mgco3 and hcl
that's also correct garnesh but i felt magnesium oxide was better
yes true, but using either MgO, MgCO3 or Mg(OH)2 is also correct... !
Separate names with a comma.