what is the reason for the chloride ion conc being 0.2?
also please can someone show me how to solve these questions! I'm so confused as to what i'm doing wrong
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the answers are A, D and C
These questions are from the sample assessment paper thank you in advance!
The sample assessment:
Q10)
a) and b) are both:
Work out excess mols then:
c=1000n/v pH = -log(c)
c) NEVER use UNIVERSAL for Acid-base titrations!
You know it's not going to be A or B now. Sort of obvious but won't be D so you could use process of elimination or work out the pH from b) and this should give you the end point, and equivalence point will be below that (hence why I'm doubting D).
Thank you, but what about for any other questions in which they ask? Is the clue in the question usually?
Yup, the question makes it clear, or they assume you have basic chemistry knowledge/common sense to know the standard states of some chemicals (e.g.- water is liquid, etc.) But most times, it should be fairly obvious, and if not, the mark scheme usually does not distinguish between aq/l in many cases if both are factually correct. Good luck!
Quick question: can you reduce a ketone/aldehyde C=O bond with excess hydrogen and a catalyst? 'Cause my notes say one thing, but a markscheme I just looked at says another
No, the H2/Pt combination reduces C=C, but not C=O. To reduce C=O, LiAlH4 is typically used.
Quick question: can you reduce a ketone/aldehyde C=O bond with excess hydrogen and a catalyst? 'Cause my notes say one thing, but a markscheme I just looked at says another
June 2014 IAL has a question regarding an organic compound reacting separately with excess Hydrogen with Nickel catalyst and LiAlH4.
You know it's not going to be A or B now. Sort of obvious but won't be D so you could use process of elimination or work out the pH from b) and this should give you the end point, and equivalence point will be below that (hence why I'm doubting D).
Ok so for a, excess moles would be 25-24.95/1000 x 1? which = 5x 10^-5
I'm really struggling with drawing titration curves! I only ever score a max of 2 in them. How do you how many units it should be and what the pH is at 25cm^3?