Mass
Mass is one of the most common measurements taken in a chemistry lab. Molar ratios and reaction rates often depend on the mass of one or more solid reactants. An electronic scale can often determine the mass of a sample to within a hundredth of a gram sometimes even a thousandth. Old-style mechanical balances are also still used in many laboratories, especially for caustic substances that threaten to spill and damage sensitive electronic equipment.
Volume
Sometimes mass is not as useful to know as volume, especially in the case of a liquid at constant temperature. Even a glass of water contains numerous contaminants that make it hard to accurately weigh the mass of the H2O alone. Erlenmeyer flasks, graduated cylinders and beakers all come with etches or marks on their sides that indicate how much of a liquid is present in terms of volume. Solutions containing an active ingredient can be diluted by changing the volume of water in which they are dissolved, making volume measurements very important.
Temperature
A great deal of chemistry is done at temperatures other than room temperature. Reaction rates and whether a reaction takes place at all are affected by temperature, which is a measurement of the heat energy emitted in a system. Especially in calorimetry, a thermometer is an essential component of a chemistry experiment. By taking the temperature of a solution before and after a reaction is carried out, the thermodynamic properties of the reactants and products can be determined. If a reaction produces a drop in temperature, it was endothermic, and if the temperature increases, it was exothermic and released energy.