Author Topic: paper 5 dilutions plzzzzzzzzz helppppppppppppppp  (Read 502 times)

Offline girl_92

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paper 5 dilutions plzzzzzzzzz helppppppppppppppp
« on: May 30, 2010, 08:56:08 am »
How do we frame our answers for this dilution stuff one eg w09/52 
and in many other places they ask about diltuing sulphurics acid prepairing 5 different solutions some1 plz help me
i woul,d be really thankful if sum1 culd provide a modal answer plz quick
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline CHEMMASTER6000

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Re: paper 5 dilutions plzzzzzzzzz helppppppppppppppp
« Reply #1 on: May 30, 2010, 09:23:15 am »
relax man. hahahaa.

anywyas so theres no sure way to structure the planing part cause wlel they always ask for somehting different. i you notice in the markscheme they only give marks for the stated question . so just follow the questoins

as for dilution , think about it this ways, if 1 solution is more concentrated the only possible reason is that it has less water or less diluted however the number of moles is the same . thus consider the eqn

moles= concentration x volume

 if both soln have the same number of moles the only difference is the volumes thus you can equate the formulaes for the two soln.

concsoln1) x vol (soln 1) = conc (soln 2) x vol (soln 2)

thus you sub in the respective concentrations vol and concentration you want into the soln and youll get the volume needed .

hope this helps pm me if you need furthur explanatoins