Please explain answers! 1) The Explanation for why CH4 is relatively insoluble i
ID: 805201 • Letter: P
Question
Please explain answers!
1) The Explanation for why CH4 is relatively insoluble in water is related to
a) the dipole dipole attraction between water molecules are stronger than the attraction between H2O and CH4 molecules
b) the size of CH4 molecules are larger than the size of H2O molecules
c) the dipole dipole attraction between Ch4 molecules are greater than teh attraction between H2O and CH4 molecules.
2) What is the value of delta H for the process MgF2(s)-->Mg+2(aq)+2F-(aq) based on the following information
delta H lattice=2922 kj/mol
delta H hyd Mg+2=-179 kj/mol
delta H hyd F-= -74 kj/mol
3) A student wishes to prepare 3.00 liters of a .200 M KCl solution (Molar mass of KCl=74.55 g/mole). The proper procedure is to weigh out...
a) 89.5 grams of KCl and add water until the final homogenous solution has a volume of 3.00 L
b) 14.9 grams of KCl and 3.00 kg of water and mix the two evenly
c) 44.73 grams of KCl and add water until the final homogenous solution has a volume of 3.00 L
Explanation / Answer
1)
a) the dipole dipole attraction between water molecules are stronger than the attraction between H2O and CH4 molecules
2) delta H = deltaH(products) - deltaH(reactants)
deltaH = -179+(2x-74)-2922
deltaH = -3249 kJ/mole
3) Molarity = (wt/Mwt) x 1/V(lit)
0.200 = (wt/74.55) x 1/3
=> wt = 44.73 g
Ans is : c) 44.73 grams of KCl and add water until the final homogenous solution has a volume of 3.00 L