Questions like "How many mg for 50 mL of 10 mM NaCl?". Mass = concentration × volume × molecular weight. Choose what to solve for.
Works out how much concentrated stock to add to reach the concentration you want. Both concentrations must be the same kind of unit (e.g. mM and µM, or 10× and 1×).
Converting µg/mL to µM (or back) needs the molecular weight. Enter one value to see it in every unit.
Used to make standard curves or IC50 concentration series. Make the first tube, then repeatedly transfer a fixed volume into the next tube (which already holds diluent).
Dissolve a powdered drug in DMSO (or another solvent) to make a stock, then work out how much to add to the medium for the concentration you want.
Uses the nmol value printed on the primer tube to work out how much water (or TE) makes a 100 µM stock.
Mix with trypan blue and count cells in the four large corner squares (1 mm² each). Record live cells (clear) and dead cells (blue) separately.