CBSE 12th Chemistry exam has to be prepared in the best possible manner so as to attain the best scores in the exam. CBSE Sample Papers for Chemistry 12th class 2015 are helpful in preparing for the exam. So, they are provided below on this page for all the interested students. The questions given below need to be solved and then it will be clear that in what all sections the improvement is required. Make a schedule for the exam and complete all the chapters in the best possible way, solving every possible type of question.
Ques1: Define the terms- a) Recemic Mixture b) Resolution c) Enantiomers
Ques2: What happens when, along with chemical reactions-
- Cyclohexanol is treated with Thionyl chloride?
- P-Hydroxybenzyl alcohol is heated with HCl?
Ques3: At 300K, 36g of glucose present per litre in its aqueous solution has an osmotic pressure of 4.98 bars. If the osmotic pressure of another solution of glucose is 1.52 bar at same temperature, what would be its concentration?
These kind of questions are often asked in the Chemistry paper. So, practice as much questions as you get.
Ques4: a) Why is alum added to water for purification?
- b) Explain why deltas are formed where river and sea water meet?
- c) Describe the preparation of colloidal solution of arserous sulphide in water.
Ques5: a) State the Raoult’s law for solution of two volatile liquids and obtain a relationship for vapor pressure of solution.
- Calculate- Molality, Molarity, Mole fraction of 20% (w/w) aqueous KI if its density is 1.2 g mL-1 (molar mass of KI= 166)
Ques6: a) How do you convert the following?
- Benzaldehyde to a-hydroxy phenyl ethanoic acid
- Ethanol to 1,3 di- hydoxy butane
b)Account for following-
- i) Carboxyl group attached to aryl & vinyl carbon increases acidic strength.
- ii) pKa of chloro acetic acid is higher than acetic acid
iii)Methanal is most reactive carbonyl compound towards nucleophiles
i)2 moles of compound (A) on treatment with strong base gives 1 mole of compound (B) and 1 mole of (C). The compound (B) on dehydrogenation with Cu gives (A) while acidification of (C0 gives carboxylic acid (D) having molecular formula CH2O2. Identify (A) to (D)
- ii) Write Equations for-
- Cross aldol condensation between propanal and ethanol in presence of dil NaOH
- Preparation of 2- methyl propan-2-ol from Grignard Reagent
Solved Sample Papers links-
Sample Paper of Class 12 Chemistry CBSE Board DOWNLOAD