Question

How many grams of sucrose, C12H22O11, are in a 94.2 mL sample of a 2.6 M sucrose solution?

Answer 1

Molar (M) means mol of solute in volume of solution (expressed by liters):


`2.6(mol)/(L)\cdot 94.2\cdot 10^(-3)\ L = 0.245\ mol`

The molecular weight of sucrose is: 12·12 + 22·1 + 11·16 = 342 g/mol.


`0.245\ mol\ C_(12)H_(22)O_(11)\cdot (342\ g)/(1\ mol) = \bf 83.79\ g\ C_(12)H_(22)O_(11)`

Answer 2

get the mass # of each element since its asking for grams
C- 12.011x12
H-1.008x22
O- 15.999x11
add all of those together to get the mass
put 2.6 moles on the top - so its the mass x 2.6 then divide by 94.2 Ml