A couple of chemistry questions about moles?

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Sonny

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how many moles of sucrose (C12H22O11) are dissolved in 2.5L of water to make a 1.M solution? How many grams of sucrose were dissolved to make the solution??

Please help!thanks!!
 
1 M = 1 mol/leter solution
so 2.5 mol sucrose
molar mass of sucrose is (mass carbon=12)x(mol carbon=12)+(mass hydrogen=1)x(mol hydro.=22)+(mass oxygen=16)x(mol oxy.=11) = 342g/mol
mass sucrose = moles sucrose x molar mass sucrose = 2.5 mol x 342g/mol = 855 grams sucrose
you just got an A on this one
 
AHAHAHHAHAHHAHAHHAHAHHAHAHHAHAHAHHA.
that first answer made me piss myself laughing...
 
molecular wt of sucrose = 270 gms

270 gms dissolved in 1 lt solution is 1 mole.
so 2.5 moles are dissolved in 2.5 lts.

then 270 * 2.5 = 675 gms are required to dissolve
 
Not many, check with your local doctor, if you live in oz you are more likely to get a melinoma than anywhere else in the world, as for sucrose its normally about 25% if memory serves me right! :)
 
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