Bihar Board Class 12 Chemistry Practical Exam 2019: Question Paper of 2018 and Tips to Score Maximum Marks
Bihar Board Previous Year Question Paper for Class 12 Chemistry Practical Exam 2019 is available here. In this article, you will get complete details related to Bihar Board Class 12 Chemistry Practical Exam i.e., evaluation scheme, list of experiments, projects work etc. At the end of this article, you will also get important tips to score well in Bihar Board Class 12 Chemistry Practical Exam.
Evaluation Scheme for Bihar Board Class 12 Chemistry Practical 2019
|Content Based Experiment|
|Class record and Viva|
Syllabus for Bihar Board Class 12 Chemistry Practical 2019
Micro-chemical methods are available for several of the practical experiments. Wherever possible, such techniques should be used.
A – Surface chemistry
(a). Preparation of one lyophilic and one lyophobic sol
Lyophilic sol – starch, gum and egg albumin
Lyophobic sol- aluminium hydroxide, ferric hydroxide, arsenous sulphide.
(b). Dialysis of sol-prepared in (a) above.
(c). Study of the role of emulsifying agents in stabilizing the emulsion of different oils.
B – Chemical Kinetics
(a). Effect of concentration and temperature on the rate of reaction between Sodium Thiosulphate & Hydrochloric acid.
(b). Study of reaction rates of any one of the following:
(i). Reaction of Iodide ion with Hydrogen Peroxide at room temperature using different concentration of Iodide ions.
(ii). Reaction between Potassium lodate, (KIO3,) & Sodium Sulphite: (Na2SO3,) using starch solution as indicator (clock reaction).
C – Thermochemistry
Any one of the following experiments
(i). Enthalpy of dissolution of Copper Sulphate or Potassium Nitrate.
(ii). Enthalpy of neutralization of strong acid (HCl) and strong base (NaOH).
(iii). Determination of enthalpy change during interaction (Hydrogen bond formation) between Acetone and Chloroform.
D – Electrochemistry
Variation of cell potential in Zn/Zn2+ || Cu2+/Cu with change in concentration of electrolytes (CuSO4 or ZnSO4) at room temperature.
E – Chromatography
(i). Separation of pigments from extracts of leaves and flowers by paper chromatography and determination of Rf values.
(ii). Separation of constituents present in an inorganic mixture containing two cations only (constituents having large difference in Rf values to be provided).
F – Preparation of Inorganic Compounds
(i). Preparation of double salt of Ferrous Ammonium Sulphate or Potash Alum.
(ii). Preparation of Potassium Ferric Oxalate.
G – Preparation of Organic Compounds
Preparation of any one of the following compounds
(ii). Di -benzal Acetone
(iv). Aniline yellow or 2 – Naphthol Aniline dye.
H –Tests for the functional groups present in organic compounds:
Unsaturation, alcoholic, phenolic, aldehydic, ketonic, carboxylic and amino (Primary) groups.
I – Characteristic tests of carbohydrates, fats and proteins in pure samples and their detection in given food stuffs.
J – Determination of concentration? Molarity of KMnO4 solution by titrating it against a standard solution of:
(i). Oxalic acid,
(ii). Ferrous Ammonium Sulphate
(Students will be required to prepare standard solutions by weighing themselves).
K – Qualitative analysis
Determination of one cation and one anion in a given salt.
Cation:- Pb2+, Cu2+ As3+, Al3+, Fe3+, Mn2+ , Zn2+, Cu2+, Co2+, Ni2+, Ca2+, Sr2+, Ba2+, Mg2+, NH4+
Anions:- CO3 2‒, S2‒, SO32‒, SO42‒, NO2‒, NO3‒, Cl‒, Br‒, I‒, PO43‒, C2O42‒, CH3COO‒
(Note: Insoluble salts excluded)
Project work –
Scientific investigations involving laboratory testing and collecting information from other sources.
A few suggested Projects.
• Study of the presence of oxalate ions in guava fruit at different stages of ripening.
• Study of quantity of casein present in different samples of milk.
• Preparation of soyabean milk and its comparison with the natural milk with respect to curd formation, effect of temperature, etc.
• Study of the effect of Potassium Bisulphate as food preservative under various conditions (temperature, concentration, time, etc.)
• Study of digestion of starch by salivary amylase and effect of pH and temperature on it.
• Comparative study of the rate of fermentation of following materials: wheat flour, gram flour, potato juice, carrot juice, etc.
• Extraction of essential oils present in Saunf (aniseed), Ajwain (carum), Illaichi (cardamom).
• Study of common food adulterants in fat, oil, butter, sugar, turmeric power, chilli powder and pepper.
Note: Any other investigatory project, which involves about 10 periods of work, can be chosen with the approval of the teacher.
After going through Bihar Board Class 12 Chemistry Practical exam’s syllabus and evaluation scheme, it is clear that you can score maximum marks if you have successfully completed the experiments assigned to you (at the time of practical exam), you have complete practical records (signed by your teacher), projects etc and you have performed exceptionally well in viva.
Here are few quick tips which will help you to score well in Bihar Board Class 12 Chemistry Practical exam 2019:
• Have an in depth understanding of concepts behind the experiments
• Learn the procedure to conduct the experiment
• Different experiments have different procedures. So, you should know how a particular experiment is to be carried out and what is the apparatus needed for that experiment.
• You must also know the name and uses of the apparatus present in the Chemistry lab
• Don’t just cram the readings
• Principle and Methodology are the frequently asked questions during viva.
• Remember important chemical reactions
• Be confident during the practical examination
• Thoroughly read the complete theory behind the experiment
• Revise your notes (also refer Class 12 Chemistry NCERT textbook also)
• Don’t be nervous at the time of experiment & write the important steps before starting the practical (you can also draw a flowchart)
• Consult with the teacher or lab attendant whenever you have any doubt