The CBSE board aims to promote understanding of basic facts and concepts among the students. To assess a student’s capability to recall facts, terms, basic concepts and answers CBSE board conducts exam. A good concept clarification, multiple revision and focusing on solving previous year question paper within the allotted time students can score decent marks. Everyone is aware of the role that good marks play in ensuring a good career and other opportunities.
Students who are weak in mathematics should concentrate more on Organic Chemistry. It is a very scoring subject. As the student can see since past few years, there has been seen that all questions are directly or indirectly asked from the NCERT books. Almost 50% of the question paper is from the textbook itself therefore NCERT books should be read thoroughly. One should remember it very well that there is no substitute to hard work. If you want to score good marks in chemistry exams a dedicated focused study needs to be adapted.
The following sequence must be followed to study chemistry:
- Solid State
- Solutions
- Electrochemistry
- Chemical Kinetics
- Surface Chemistry
- General Principles and Processes of Isolation of Elements
- p-Block Elements
- d and f Block Elements
- Coordination Compounds
- Haloalkanes and Haloarenes
- Alcohols, Phenols and Ethers
- Aldehydes, Ketones and Carboxylic Acids
- Organic Compounds Containing Nitrogen
- Biomolecules
- Polymers
- Chemistry in Everyday Life
In everyday life most of the mixture contains two or more pure substance. It is near to impossible to find substance in its purest form. The homogeneous mixture of two or more components is called solutions. Homogeneous mixture can be defined as mixture of two components in equal parts meaning it should be uniform throughout the mixture. The next topic comes as what is solute and solvent. Solvent is the largest most component of the solution. Since it is the largest composition of the mixture it also gives it the physical state. Any other part in the solution which comprises of small part is called solute.
Solutions are of three type namely gaseous solutions, liquid solutions and solid solutions. Now in gaseous solution the solvent has to be gas. The solute on the other hand can be a gaseous one or a liquid one or a solid one. Examples of gaseous solvent and gaseous solute is mixture of oxygen and nitrogen gases. Similarly, example of gaseous solvent and liquid solute is chloroform mixed with nitrogen. Similarly, example of gaseous solvent and solid solute is camphor in nitrogen gas.
Again, in liquid solution the solvent is liquid while the solute can be liquid, solid or gaseous in nature. Now the example of liquid solvent and liquid solute is ethanol dissolved in water, example of liquid solvent and gas solute is oxygen dissolved in water. example of liquid solvent and solid solute is glucose dissolved in water.
Again, in solid solution the solvent is solid while the solute can be liquid, solid or gaseous in nature. Now the example of solid solvent and liquid solute is amalgam of mercury with sodium, example of solid solvent and gas solute is solution of hydrogen in palladium. example of solid solvent and solid solute is copper dissolved in gold.
The concentration of a solution can be mainly expressed in terms of
- mole fraction
- molarity
- molality and
- percentages
other than there one need to know about the concept of henry’s law. It states that the solubility of gas in liquid is directly proportional to the partial pressure of the gas.
Certain concepts related to Raoultslaw,vapor pressure needs to be known. Any solution that obeys Raoults law can be identified as an ideal solution. Positive and negative deviation can be observed from Raoults law. The concept of azeotropes can be observed due to very large deviation due to Raoults law. Now what are the colligative properties? It can be defined as a property of solution that is independent of their chemical identity and mainly depends on the number of solute particles. colligative properties can be used to define the molar masses of the solute.
While self-study is extremely important, students are advised to refer to coaching notes for further clarification and assessment. Doubtnut.com is one such online platform that provides a comprehensive, in depth and most importantly focused study for students from grade 6th to 12th. It also specializes in providing coaching for JEE and NEET competitive exams. Online classes are provided at a minimal cost. Periodical quizzes and test are held for self-assessment. It provides video solutions for the students who attend video lectures. As the videos are uploaded every day, students can go through multiple such video solution covering various topics. The Doubtnut app can be downloaded from Google play and App Store.
Important question: The vapour pressure of a dilute aqueous solution of glucose is 750 mm of mercury at 373 K. The mole fraction of solute is?