Pharmaceutical Calculations pp 113-155 | Cite as

# Mixture Problems in Pharmaceutical Sciences

## Abstract

In this chapter, I have approached general mixture composition problems as regular mathematical mixture problems. Equations are developed to represent the different rates and quantities of the variables that are involved in the mixture problems. These equations are used to identify the domain of all variables and develop a procedure to provide all possible answers. You will learn to identify the type of variables that are preserved during the initial and final states of a process, construct equations that represent the initial and final states of these variables, and solve the system of linear equations to determine the specific values of these variables. You may skip the three- and four-component mixture composition problems if you feel that you will not be needing those and move to the empirical methods of alligation. The obscured method of alligation alternate is unraveled for the first time. The rules of the method and the advantages and disadvantages of it are clearly explained, and their application is herein expanded to other areas such as physical chemistry, pharmacokinetics, and pharmacoeconomics.

## Keywords

Mixture problems Alligation medial Alligation alternate Mass balance equation## Supplementary material

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## References

- A. Bregman, Alligation alternate and the compositions of medicines: Arithmetic and medicine in the early modern England. Med. Hist.
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