Question

4 gram of NAOH is dissolved in 162 gram of H2O determine mole fraction of NAOH

Answer 1

given,
4 g of NaOH
162g H2O
formula for mole fraction Xa=Na/Na+Nb (Xa is the mole fraction of NaOH,Na is the no of moles of NaOH,Nb is the no of moles of H2O)
No of moles is given by weight of substance/molar mass of substance
Substituting the above information,
Na is 4/40
Nb is 18/162
therefore Xa is 0.1/0.1+0.1)
=0.5