Reaching the concluding point of your schooling, board exams are a much-hyped monster ready to evaluate what you have learned in the final year of your senior secondary education. For those studying science stream subjects, an effective way to test your classroom learning is through practical examinations which happen alongside the written exams. Holding around 30% weightage of the total marks, these practicals are conducted by an invigilator or external who comes from another school and is assisted by the subject teacher. So, as the board exams are nearing your way, we are here to your rescue! This blog aims to elaborate upon the process of acing the chemistry practical for class 12th, the topics you must study as well as helpful tips that can guide you in acing this exam.
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Marking Scheme
Before moving on to the main concepts, take a look at the following table which shows a general bifurcation of marks for chemistry practical in class 12th:
Sections | Marks |
Salt Analysis | 08 |
Volumetric Analysis | 08 |
Project Work | 04 |
Content-Based Experiment | 06 |
Viva Questions and Class Records | 04 |
Total | 30 |
List of Experiments for Chemistry Practical in Class 12th
Since it is more of a laboratory examination, a Chemistry Practical aims to evaluate a candidate’s knowledge of theoretical concepts through their efficiency at carrying out the prospective experiment. From preparation of inorganic and organic compounds to chromatography, all the key subjects in Chemistry are put to test. Take a look at the following list of different topics covered in a Chemistry Practical:
Experiments | Basic Explanation |
Salt Analysis/Qualitative Analysis | Also referred to as systematic qualitative analysis or qualitative inorganic analysis, the Salt Analysis is actually carried out with a series of tests in a systematic manner in order to identify the cation and anion of an inorganic salt. |
Titration (Mohr’s Salt) | The titration experiment aims to find out the strength of a given potassium permanganate solution against the standard ferrous ammonium sulfate or Mohr’s salt solution. |
Carbohydrate Test | Regarded as the most abundant as well as diverse organic compounds, Carbohydrates have an imperative role in establishing and evolution of life on earth as they create a direct link between the sun and chemical energy. This experiment aims to study various simple tests of carbohydrates in a provided sample. |
Chromatography | There are two chromatography experiments in the Chemistry Practical: -Separating pigments from leaf and flower extracts using paper chromatography as well as evaluating Rf values. – Separating the elements of an inorganic mixture which comprises two cations only. |
Preparing Colloidial Starch | This preparation experiment focuses on preparing the lyophilic sol of starch. It focuses on how starch creates sol when water is applied as a dispersion medium. Further, this formation of sol is boosted by putting it on heat. Also, the mixture of water and starch must be heated at 100° C to form sol. |
Oil Fat Test | You will be given a food sample in which you will be testing the presence of oils and fats. This experiment is based on the theory of fats and oils are greasy and when put under hydrolysis with aqueous or alcoholic sodium or potassium hydroxide, they release glycerol. There are five main tests carried out for this experiment, i.e. -Solubility Test -Baudouin Test -Acrolein Test -Hubble’s Test -Translucent Sport Test |
Hydrochloride | Preparation of Colloidal Ferric Hydroxide which is based on the main theory that Ferric Hydroxide forms lyophobic sol when water is used as a dispersion medium. |
Volumetric Analysis- Preparing Mohr Salt Crystals & Potash Alum Crystals | In this experiment, an unknown solution is given and analysed to determine the quantities of its constituents with the help of measurement of volumes of the chemical solutions taking part in the chemical reaction. |
Protein Test | This chemical experiment focuses on testing the presence of protein in a food sample provided to students. |
Titration (Oxalic Acid) | In this experiment, the titration of potassium permanganate is carried out against oxalic acid. This elucidates an example of Redox Titration. |
Don’t Forget to Check Out How to Ace Physics Practical in Class XIIth!
Important Tips & Tricks for Acing Your Chemistry Practical
Now that you are aware of the key concepts and topics that will be asked in this practical examination, there are some other things that you should remember during your preparations. We have listed down some of the major tips and tricks that can help you crack your chemistry practical successfully:
Master Your Conceptual Understanding of Each Experiment
Gearing up for the final showdown which will be facilitated by an external examiner, you must put your best foot forward. It becomes important to thoroughly understand and learn the concept behind the varied chemistry experiments that you can be asked about. For instance, you can remember the aim of the experiment which can further assist you in recalling the procedure. So, during the chemistry practical, you won’t be just blurting out statements but elaborating with a clear understanding.
Remember the Stepwise Procedure
Since there are many experiments to retain in your memory, you must begin by breaking them into simple steps that you can easily learn. Then, make notes of what the result of each step would be in an experiment. During the chemistry practical, do not forget to choose the right set of apparatus as the wrong one may lead to a deduction in marks. For instance, in the experiment of converting ethane to ethanoic acid, the stepwise procedure would be:
- Convert ethane to chloro-ethane using the chlorine gas in the presence of sunlight,
- Chloro ethane to ethanol with the help of aqueous KOH,
- Final step would be to convert ethanol to ethanoic acid by mixing it with alkaline potassium permanganate.
Avoid Mugging Up Experiments & Readings
Clearing your basics thoroughly is a better option rather than just cramming every experiment. There will be times when the readings obtained from a specific experiment may not come out to be the same every time. The probable reason for this could be a change in the apparatus. As the apparatus would be provided on the spot, hence, it is not advised to mug up any readings completely. Students must wholly practice each experiment so that they can obtain precise readings. If you need tips to learn fast, then check out our blog on how to memorize fast?
Take Help of Visuals & Diagrams
Keeping in mind the different learning methods, visual learning is one of the best ways to retain complicated concepts. Draw neat diagrams to remember what apparatus and set up would be used. You can also watch online tutorials for chemistry practicals that explain difficult experiments in a much simpler manner. This way, you can get familiar with placing your apparatus correctly as you may be asked to set it up differently.
Viva Questions for Chemistry Practical
The viva section is an important component in every practical chemistry exam. So, if you wish to score well in your chemistry practical, you need to perform well in your viva section too. So, given below are some basic viva questions which will give you an idea regarding what kind of questions can you expect to be asked.
- What is the equivalent mass of KMnO4 when it acts as an oxidizing agent in an acidic medium?
- What volume of 10M HCl must be diluted with water to get 1L of 1M HCl?
- It is customary to read lower meniscus in case of colourless and transparent solutions and upper meniscus in case of highly coloured solutions, why?
- What type of flame would you use for general heating purposes?
- Are ‘molality’ and “molarity’’ same?
- What are acidic and basic radicals?
- Why does inorganic salt ionise when dissolved in water?
- What type of bond is present in an inorganic salt?
- What is Lucas reagent?
- What is the main product obtained when aniline is treated with chloroform and caustic potash?
Thus, we hope that this blog has helped you gain an understanding of what you can expect from your chemistry practical and how you can successfully ace it. Needless to say, qualifying for the tertiary education stage, it is normal to feel confused about the field you want to study. Let our Leverage Edu experts guide you in finding a suitable undergraduate program as well as university that can help you begin your career journey in the right way.