Complex chemical reactions you study in chemistry courses aren't just scientific novelties. They're the products of interactions that can be represented using equations. Consequently, algebra and chemistry functions are inextricably linked, and students generally need a basic understanding of algebra to be able to dissect chemistry problems and understand what's behind a chemical reaction.
Equations

Many basic chemistry problems can be solved with simple equations, and a student will need to know how to solve for and manipulate a variable to get the right answer. For example, D=m/v summarizes the relationship between density, mass and volume. A student who knows two of the variables can solve for the third if she understands algebra.
Conversion

Chemistry students are sometimes faced with numbers presented in different units. For example, a student might be given the volume of a cylinder in ounces and milliliters. Students can easily convert between number systems using simple algebra if they know the formula for converting one number system to another. For example, the proper conversion from milliliters to liquid ounces can be represented as y (where y equals ounces) = x (where x is the number of milliliters) * 0.033814.
Dimensional Analysis

Chemistry relies on both algebra and geometry, and students will need to apply algebra to geometry. For example, a student who has a specific number of units of a chemical and who needs to discern how many more units they need can use a process called dimensional analysis. This requires that students know the right formulas to use and that they have the algebra skills to know how to apply the formulas and cancel out irrelevant units.
Mathematical Thinking

Algebra teaches students how to think in an orderly, logical manner. Solving an equation step by step and mastering abstract thinking can both help students excel in chemistry. When students solve equations for chemical reactions, for example, their practice solving algebraic equations can help them avoid making an error, and their understanding of abstract mathematics can help them understand what each component of the equation represents in the physical world.
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