Solving previous years’ board question papers is a perfect practice to give an edge to your board exam preparations. It helps you to acquaint with important questions and the conceptual topics from which questions are frequently asked in exams. It also lets you analyse your weak and strong areas so that you may amend your preparations accordingly.
In this article, we are providing the Rajasthan Board Class 12 Chemistry Solved Question Paper 2018. All the solutions provided here are explained in a way to help students easily understand the concepts/theories used thus making the exam preparations easy and effective.
Key features of Rajasthan Board Class 12 Chemistry Solved Question Paper 2018 are
- Simple and stepwise solutions are provided for each question
- Appropriate concepts have been used in solutions
- Chemical equations are written correctly
Structure of Rajasthan Board Class 12 Chemistry Paper 2018 is as per the following table:
| Part |
Question Nos. |
Marks Per Question |
| A |
1 – 13 |
1 |
| B |
14 – 24 |
2 |
| C |
25 – 27 |
3 |
| D |
28 – 30 |
4 |
Question number 21, 27, 28, 29 and 30 have internal choices.
A few sample questions and their solutions are given below:
Q. Write full name of DDT.
Ans.
DDT – Dichloro Diphenyl Trichloroethane
10. Write IUPAC name and chemical formula of Acetone.
Ans.
IUPAC name of Acetone: Propan-2-one
Chemical formula of Acetone: CH3COCH3
Q. Arrange the following compounds in the descending order of their reactivity towards nucleophilic substitution reaction.
CH3CHO, HCHO, CH3COCH3
Ans.
Aldehydes are usually more reactive toward nucleophilic substitutions than ketones because of both steric and electronic effects. Further in aldehydes, the reactivity follows the order: primary > secondary > tertiary.
Thus the correct order of reactivity is:
HCHO > CH3CHO > CH3COCH3
Q. (A) Aspirin should not be taken in empty stomach, why?
(B) Write any two differences between dyes and pigments.
Ans.
(A) If you don't eat before taking an aspirin, you may get some stomach irritation, followed by a stomach ache. This happens because there is low acid level in the stomach which is maintained by the intake of food to dissolve the aspirin. So aspirin should not be taken on an empty stomach.
(B) Differences between dyes and pigments:
| Dyes |
Pigments |
| Most of dyes are organic. |
Most of pigments are inorganic. |
| Dyes have direct affinity to textile material. |
They have no direct affinity to textile material. |
To download the completely solved paper, click on the following link:
| Rajasthan Board Class 12 Chemistry Solved Question Paper 2018 |
The solved Chemistry question paper 2018 given here will offer a variety of problems to solve and give you the practice to code and know what kind of questions might be asked in the board exam 2019.
To get more of such important articles for Rajasthan Board Class 12 Examination 2019, click here.
