Search results
Results from the WOW.Com Content Network
The relative activity of a species i, denoted a i, is defined [4] [5] as: = where μ i is the (molar) chemical potential of the species i under the conditions of interest, μ o i is the (molar) chemical potential of that species under some defined set of standard conditions, R is the gas constant, T is the thermodynamic temperature and e is the exponential constant.
The cell concentration needs to be known for many experiments in molecular biology, in order to adjust accordingly the amount of reagents and chemicals that are to be applied in the experiment. Studies that examine the growth rate of microorganisms (in other words, how fast they divide to create new cells) require cell counting.
In the standard addition method, a standard (usually in the form of a solution) with a known concentration is added in increasing increments to a set of solutions containing the same unknown analyte.The matrix for these solutions are identical which eliminates the matrix effect from changing the signal of the analyte when measured. For this ...
The general expression Qualitative Analysis [...] refers to analyses in which substances are identified or classified on the basis of their chemical or physical properties, such as chemical reactivity, solubility, molecular weight, melting point, radioactivity properties (emission, absorption), mass spectra, nuclear half-life, etc. Quantitative Analysis refers to analyses in which the amount ...
Enzyme assays can be split into two groups according to their sampling method: continuous assays, where the assay gives a continuous reading of activity, and discontinuous assays, where samples are taken, the reaction stopped and then the concentration of substrates/products determined. Temperature-controlled cuvette holder in a spectrophotometer.
The solubility of a specific solute in a specific solvent is generally expressed as the concentration of a saturated solution of the two. [1] Any of the several ways of expressing concentration of solutions can be used, such as the mass, volume, or amount in moles of the solute for a specific mass, volume, or mole amount of the solvent or of the solution.
Titer (American English) or titre (British English) is a way of expressing concentration. [1] Titer testing employs serial dilution to obtain approximate quantitative information from an analytical procedure that inherently only evaluates as positive or negative.
Volume percent is the concentration of a certain solute, measured by volume, in a solution.It has as a denominator the volume of the mixture itself, as usual for expressions of concentration, [2] rather than the total of all the individual components’ volumes prior to mixing: