In chromatography, the Rf value represents the ratio between the migration distance of a substance and the migration distance of the solvent front. Rf is a coefficient called retention factor and has values that range between zero and 1.
Know MoreRf quantifies the distance that each compound of the analyzed mixture has traveled. The higher the Rf value, the longer the distance that a specific compound has traveled. The solvent front always moves further than any of the compound in the mixture. However, the compounds migrate differently depending on the type of mobile phase used because the migration speed depends on some characteristics of the solvent, such as polarity. The Rf value is characteristic for any chemical compound.
Learn MoreIn math, a dependent variable is one in an expression, equation or function that depends upon one or more other variables' values to determine its value. The dependent variable is usually isolated on one side of an equation. For example, "x" is the dependent variable in the equation x=y+1.
Full Answer >The domain and range of a function designate the values at which the function exists. In a composite function, one function is being applied to another. You must determine values at which the first function does not exist and values for which the first function creates values where the second function does not exist. This process usually takes only a few minutes to complete.
Full Answer >A solution set is all of the values that solve an equation. If there are no solutions for an equation, the solution set is referred to as the null or empty set.
Full Answer >An ellipse is graphed in a coordinate plane by determining its center and the x- and y-coordinates for one point along the ellipse and then plugging those values into an appropriate formula. One formula for graphing an ellipse is (x - h)^2/a^2 + (y - k)^2/b^2 = 1.
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