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@Dexter
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iteachchem
Transcription requested by MasterChief
Write down the definition of all of these things, right. Molarity is what? Number of moles of solute divided by volume of solution. That is the important thing here. Numerator you have got solute, nominator you have got solution, okay. And what is density? Density is mass of solution divided by volume of solution. Now this is where things get interesting. If you divide the mass of the solution by molar mass, does that really give you a molarity? Check the units. I mean, you are mentioning that this is the formula, I am just going with what you have told me, right. May be right, may not be right. I am not sure. Can you write down the entire formula for everything, including the units, by units I mean of what? Moles of what? Solution divided by, you know, litre of solution, volume of solution. That is what molarity is. So density has mass of solution divided by volume of solution. Now dividing the mass of solution by molar mass of solute, that does not make sense to me. So that is what I am saying. Are you sure this is a formula?
n/vol of solution = Molarity where n stands for no. of moles. --- let this be eq 1
density = m/volume
number of moles = mass of compound or element/ molar mass
so in 1st eq mass of compound/ (molar mass * vol of solution)
= density/ molar mass
understood?
this will be wrong no, since we are dividing mass of solution by molar mass to get no of moles which is wrong (no of moles = total mass of solute/ molar mass)
as mentioned here formula is probably wrong
I was also confused by that so I asked it. I was refering to this ques solution before I got ocnfused
Can you explain this ?
can you try the question out from first principles?
density given so you know what mass of solution ispresent in 1 l solution.
and hence, you know its molarity assuming it is 100 % methanol that is what they have done
793/32
now you dilute that to get 2.5 l solution of given molarity
so it means like density is present for 1 litre solution thats why molarity and no of moles are equal. Am I right ?
as molarity = no of moles / volume of solution
and If we take 1 litre
molarity = no of moles
wht do u mean? i dont get ur point
mass of solution comes in ml etc u can convert that to gram etc.. i dont get your point.
na it is cos it is wholly just methanol
nothing else, no water
im saying u cant divide mass of solution (considering density of soln is given) by molar mass of solute to get no of moles
we good?
@Abhi
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