When a solid solute is placed in a solvent, the solvent particles completely surround the surface of the solid solute.
If attractive forces between the solute particles and the solvent are greater than the attractive forces holding the the solute particles together, the solvent particles pull the solute particles apart and surround them.
+ - - - NaCl Na = Cl = H 2 O H = O = + - + Process of Solvation - + + - + + + - - + + - + - - + - + - + - + - + + - + + - + + - + + - + +
Average Atomic Mass (How the number ends up on the periodic table!!) 1 st Mass of one isotope x % abundance in decimal form (watch SIG FIGS!!) 2 nd Do this for each isotope of that element 3 rd Add all individual isotopes together to get the average atomic mass of the element.
1. Calculate the average atomic mass of potassium using the following data: Potassium-39 38.964 amu x 0.9312 = 36.28 amu Potassium-41 40.962 amu x 0.0688 2.82 amu = + Average atomic mass for K = 39.10 amu 6.88 % 40.962 amu Potassium-41 93.12% 38.964 amu Potassium-39 % abundance Mass Isotope
2. Calculate the average atomic mass of magnesium using the following data: Magnesium-24 23.985 amu x 0.7870 = 18.88 amu Magnesium-25 24.986 amu x 0.1013 2.531 amu = + Average atomic mass for K = 24.31 amu + Magnesium-26 25.983 amu x 0.1117 = 2.902 amu 11.17 % 25.983 amu Magnesium-26 10.13 % 24.986 amu Magnesium-25 78.70% 23.985 amu Magnesium-24 % abundance Mass Isotope