Crystallization experiment

We will be conducting a crystallization experiment this week. I was wondering what the most common materials used for this experiment are and what are their best solvents.

Thanks from Sheryl


alum in water is really good, however, it takes some time for the water to evaporate.



I have done a fractional crystallization using KClO3 and CuSO4*5H2O. It is possible to obtain WHITE KClO3 (not blue from contaminating CuSO4).

  1. 👍 0
  2. 👎 0
  3. 👁 450
  1. 1. Why is the final product from the crystallization process isolated by vacuum filtration and not by gravity filtration? 2. Environmentally speaking, what are the advantages and disadvantages of recrystallization versus column chromatography? Recrystallization –Report Form

    3. Explain, in your own words, why dissolving and then reforming crystals improves the purity of those crystals. 4. Explain why a solvent that can dissolve the solute, even when it is cold, is useless for recrystallizations.

    1. 👍 0
    2. 👎 0
  2. The vacuum produces a lower pressure which cools the solution and promotes crystallization. Also, it dries the crystal well. When you are using a vaccum, you decrease the pressure from the lower side of the filter, keeping a big pressure difference which makes the solvent pass through the filter quickly, regardless of the amount of solution above the filter.
    This way you minimize the residual amount of solvent in your solid product, but also avoid losses due to temperature increase. Vacuum filtration is used instead of gravity filtration in order to achieve a dryer product in less time. The faster process of vacuum filtration allows the slurry to remain cold and in cases such as with benzoic acid more crytals will remain formed at colder temperatures.

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. Science

    1. The ? is the part of an experiment that is not being tested and is used for comparison. (7 words) 2. The ? describes the steps you use during an experiment. (9 words) 3. After an experiment, scientists write a ? which

  2. Chemistry

    A student performs a crystallization on an impure sample of biphenyl. The sample weighs 0.5 g and contains about 5% impurity. Based on his knowledge of solubility the student decides to use benzene as the solvent. After

  3. chemistry

    consider a crystallization of sulfanilamide in which 10 mL of hot 95% ethyl alcohol is added to 0.10 g of impure sulfanimide. after the solid has dissolved, the solution is cooled to room temp. and then placed into an ice-water

  4. chem

    why do we add boiling chips or boiling stones before the distillation starts? Boiling chips should never be added to a hot solution!Why? i don't know what the answer is to the first one, but as for the second i think i have a

  1. Science

    A scientist studying the effects of gamma rays on marigolds gathered the data shown below. Hypothesis: Marigolds exposed to higher levels of radiation will not grow as well as marigolds that are exposed to less radiation Plant A:

  2. math

    Scientists are conducting an experiment with a gas in a sealed container. The mass of the gas is measured, and the scientists realize that the gas is leaking over time in a linear way. Six minutes since the experiment started, the

  3. Science

    A scientist studying the effects of gamma rays on marigolds gathered the data shown below. Hypothesis: Marigolds exposed to higher levels of radiation will not grow as well as marigolds that are exposed to less radiation Plant A:

  4. Math

    Zoe keeps track of the miles per gallon her car gets per week. She has accumulated the following data: (1, 24), (2, 24.38), (3, 24.76), (4, 25.14) A. The common difference is 0.38 B. The common difference is 0.76 C. The common

  1. science

    Sandra is conducting an experiment on the speed of toy cars and how they are affected by the type of surface they are placed on. Sandra measures the distance each car travels on carpet, tile and hardwood floors. She also records

  2. Chemistry

    A student who was isolating aspirin stopped the experiment after filtration step alumina. One week later, the methanol was evaporated and the experiment was completed. The melting point of the aspirin was found to be 110-115

  3. science

    Examine the situation. Lloyd is studying the effect of breakfast cereal on the health of rats. He suspects that the cereal may be unhealthy. He feeds rats various amounts of breakfast cereal over a six-week period. He weighs the

  4. Organic chemistry

    A diels-Alder reaction of cyclopentadiene with Maleic Anhydride experiment was conducted in lab. But I was wondering why we added ligroin to the maleic anhydride and ethyl acetate. I know ligroin can be used as a solvent and it is

You can view more similar questions or ask a new question.