## To calculate the percent yield of a reaction, you need to know the actual yield and the predicted yield. The actual yield is the amount of product obtained in the reaction, typically measured in grams or moles. The predicted yield is the theoretical amount of product that would be obtained if the reaction proceeded perfectly, based on stoichiometry.

The formula to calculate percent yield is:

Percent yield = (actual yield / predicted yield) x 100

To find the number of millimoles (mmol) of a substance, you first need to determine the number of moles (mol) of that substance. The number of moles can be calculated using the formula:

Moles = mass / molar mass

Where mass is the amount of substance measured in grams, and molar mass is the mass of one mole of that substance, usually measured in grams/mole. This formula allows you to convert between mass and moles.

Once you have determined the number of moles, you can convert it to millimoles by multiplying by 1000, since there are 1000 millimoles in one mole.

Millimoles = Moles x 1000

In titrations, you can also determine the number of millimoles using the equation:

Milliliters x Molarity = Millimoles

Where milliliters is the volume of the solution used in the titration, and molarity is the concentration of the solution in moles per liter. This equation allows you to calculate the number of millimoles from the volume and concentration.