What is a good percent recovery for recrystallization?

What is a good percent recovery for recrystallization?

According to wikipedia, the usual yield of a hot water recrystallization of benzoic acid is 65%, though that is under ideal conditions. Based on that, a recovery of 54% is fairly good, especially if that was your first attempt. Also, what happens during recrystallization?

Is a 45% yield ever a good percentage yield?

Think of percent yield as a grade for the experiment: 90 is great, 70-80 very good, 50-70 good, 40-50 acceptable, 20-40 poor, 5-20 very poor, etc.

What is an ideal percent recovery?

There are two cases of percent recovery yield: below 100% and above 100%. The value above 100% is the inaccurate value due to erroneous calculation/weighing. The value below 100% is usually the desired value.

Is a percent yield over 100 reasonable?

The actual yield is the amount of product that is actually formed when the reaction is carried out in the laboratory. However, percent yields greater than 100% are possible if the measured product of the reaction contains impurities that cause its mass to be greater than it actually would be if the product was pure.

What is the difference between percent yield and percent recovery?

Percent yield is the ratio between percentages of actual yield and the theoretical yield of the final product obtained from chemical synthesis. Percent recovery is the amount of a product obtained after its synthesis and purification. Percent yield can be used to determine the efficiency of chemical synthesis.

What is considered a good percent yield?

According to the 1996 edition of Vogel’s Textbook , yields close to 100% are called quantitative, yields above 90% are called excellent, yields above 80% are very good, yields above 70% are good, yields above 50% are fair, and yields below 40% are called poor.

Is 65% a good yield?

A higher percent yield might signal that your product is being contaminated by water, excess reactant, or another substances. A reaction yield of 90% of the theoretical possible would be considered excellent. 80% would be very good. Even a yield of 50% is considered adequate.

What is the formula for percent recovery?

Percent recovery = amount of substance you actually collected / amount of substance you were supposed to collect, as a percent. Let’s say you had 10.0g of impure material and after recrystallization you collected 7.0 g of dry pure material. Then your percent recovery is 70% (7/10 x 100).