What is chromatography used for?
Define an isotope.
Which describes fractional distillation as you move up the column?
What type of ion does an atom form when it gains electrons?
Why are atoms electronically neutral?
Who discovered the atom was mostly empty space and how?
What type of ion does an element in Group 3 form?
What techniques can be used to separate rock salt?
Why is the line in chromatography drawn in pencil?
How many electrons can the first four shells hold in total?