No. mole fraction NaCl = moles NaCl/total moles.
moles NaCl = grams/molar mass NaCl
moles H2O = 300/molar mass H2O
1) If exactly 100.0 grams of NaCl (mm=58.44g/mol) are dissolved in 300 grams of water (mm=18.02g/mol), the mole fraction of NaCl is?
a) 1.71
b) 0.0932
c) 0.250
d) 0.103
e) 4.75
I did 100g / 100g + 300g = 100/40 = 0.250.
Did I do this correctly?
5 answers
Ok so 100/58.44= 1.71
yes. 1.71 mol NaCl
300/18.02 = 16.65
XNaCl = 1.71/(1.71+16.65) = ?
300/18.02 = 16.65
XNaCl = 1.71/(1.71+16.65) = ?
Ok now I got 0.0931, so this is the mole fraction for NaCl?
yes.