- How to use
**the Mass Balance Equation**for reactive and unreactive chemical processes. - Be able identify a process as either a
**Batch or Continuous.**

Explanation: Concentration tells us how much of one component (in a mixture) we have relative the mixture (or another component in the mixture). That is, for a mixture of sugar and water, a concentration can specify how much water we have relative to the solution (water and sugar), or how much water we have relative to the other component (sugar). These concentrations can be expressed using units of amount (mols, molecules, ...), mass (kg, lb, ...), and volume (m ^{3}, lb_{m} / ft^{3}, kg / in^{3}, ...^{3}, lb-mol / ft^{3}, g-mols / LThe last molar concentration listed, g-mol/L is the Molarity of the solute in the mixture. Thus, the definition of molarity follows: Molarity of component A, _{A} = g-mol_{A} / L_{total}Mass and Mole FractionsMass and mole fractions will be used frequently in material and energy balance problems. The notation used in the course and thus the notation used here differs from the notation introduced in chapter 3 (here, x designates a liquid or solid mass or mole fraction, and y designates mass or mole fraction for a gas). Here are the definitions for mass and mole fractions: Equation 1: x_{A} = m_{A} / m_{total}
Equation 2: x_{A} = n_{A} / n_{total}
Equation 3: y_{A} = m_{A} / m_{total}
Equation 4: y_{A} = n_{A} / n_{total}
x "x" is used for liquids and solids, thus the first two equations are the mass and mole fractions for liquids and solids. Accordingly, the last two equations refer to gases. As you can see, "x Related to the mass and mole fractions are the units of parts per million (ppm) and the parts per billion (ppb). Here, we simply multiply the mass or mole fraction by 10 parts per million ^{6}parts per billion ^{9}
A mixture of gases has the following composition by mass: OAnd, for mass fractions, we would move the decimal place over two places, so, for example, the mixture is 16% O _{2}, or we could say, the mole fraction of O_{2} in the mixture is .16. Determine the molar composition of this mixture. (hint: you first need to find the total moles of the mixture)
Calculate the average molecular weight of air. Air is 79% N _{avg} = y_{N2}MW_{N2} + y_{O2}MW_{O2}
A material balance problem (chapter 4) gives us the following quantities of compounds going into a condenser. Determine the mole fractions of each stream.PLACE "CONCEN BMP" HERE |

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