Please help........?

Question

I've one chemistry problem . If u don't know then wright i don't know i'll get to know that how many people have the courage to solve this simple question. My question is:-
500centimetre cube of a given soln s contains 9.0 gram of glucose(C6H12O6). What is the molality of the soln.?
Formula for molality is :-
Molality = mass of solute
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( gram molecular mass of solute).(mass of solvent)
Molecular mass of glucose is 180.

Answer 1

this sounds like homework. i havent had chemistry in 10 years.

your formula for molality is either confusing or wrong.
http://www.nyu.edu/classes/tuckerman/honors.chem/lectures/lecture_12/node5.html

here's my attempt.
9 g glucose X (1 mole glucose/180 g glucose ) X (1/500 cm^3 water) X (1g water/1 cm^3 of water) X (1,000g/ 1 kg) gives
9 /180/500*1,000 = .1 Molality
and the units works out to moles glucose/1 kg water

hmmm, may have to subtract the 9 g glucose from the weight of the water. but does less water fill in 500 cm^3 if glucose is mixed in? i don't think so.

so we have 9/180 for the moles of solute for the top part
and for kg's of solvent we get 500 g - 9 g =491 g = .491 kg water
giving 9/180/.491 =.102 Molaliliy

Answer 2

Well Mini,
First of all molality is moles of solute/Kg of solvent
so m= 1000* mass(solute) / (MW(solute)*mass(solvent)) if mass(solvent) is also expressed in grams

You don't say which is the solvent and the density so how can we convert volume to mass?

Answer 3

i do know how to do it,
but I have my own hw to do

and by the way it should be "if you don't know then WRITE i don't know" because w-r-i-g-h-t is a last name (as in wright brothers) w-r-i-t-e is as in hand writing