Posted by bf on Sunday, January 24, 2010 at 11:30pm.
now am stuck on how to find the grams of X+Y=1.10
X for glucose and Y for sucrose
i had 3.78=M0.08206*298
3.78/24.45=0.1546M
0.1546*0.025=0.003865 moles. now am stuck. help please

chemistry  DrBob222, Sunday, January 24, 2010 at 11:42pm
First mistake.
3.78 = M*0.08205*298
Solve for M.
Then M = moles/L
L = 0.025, not 24.45.
Then you solve two simultaneous equations which I set up earlier. It becomes a math problem then, and not a chemistry problem. I assume you know how to solve two equations simultaneously.
(X/180) + (Y/342) = moles
X + Y = 1.10 grams.
========================
Solve equation 2 for, say, X.
X = 1.10  Y
Now substitute X (which is now 1.10Y) into equation 1 and solve. The X will disappear, Y will be what you solve for, then substitute Y back into equation 2. You now have X and Y; ;i.e., grams glucose and grams sucrose. Then you can do percent from this.