Question: Define Geometric Isomerism
Answer: Geometric isomerism is a type of stereoisomerism that occurs when two or more molecules have the same molecular formula and molecular structure, but the spatial arrangement of atoms within the molecule differs. This type of isomerism is most common in compounds with double bonds, but can also occur in compounds with single bonds.
Question: Why phenols are acidic.
Answer: Phenols are acidic in nature because they contain an electrically charged group of atoms called a hydroxyl group (–OH). This group can easily donate a proton (H+) when exposed to a base, making the molecule more acidic.
The boiling point of halo-alkanes are in the order
Answer: 1. Methane (CH4) 2. Ethane (C2H6) 3. Propane (C3H8) 4. Butane (C4H10) 5. Pentane (C5H12) 6. Hexane (C6H14) 7. Heptane (C7H16) 8. Octane (C8H18) 9. Nonane (C9H20) 10. Decane (C10H22)
Chemistry: Solved Previous Year’s Question Paper for NCERT/CBSE Class 12th Chemistry Paper Code (HSEIIRKO-13-X) Long Answer Type Questions (Each carries 5 Marks) Question: Discuss briefly the oxidation states of the 3d-transition series. Answer: The 3d-transition series is composed of elements from the fourth period of the periodic table, including scandium (Sc), titanium (Ti), vanadium (V), chromium
Define Calcination? Give an Example?
Answer: Calcination is the process of heating a solid substance to a high temperature to drive off its volatile components or to achieve a desired chemical or physical change. An example of calcination is the process of roasting gypsum to produce plaster of Paris.
Question: How Polythene is prepared
Answer: Polythene is prepared through a process called polymerization. This process involves the combination of two or more monomers (small molecules) to create a larger molecule. The monomers used to create polythene are typically ethylene, which is derived from natural gas or petroleum and can be combined through a variety of different methods. The result is a plastic that is lightweight, yet strong and durable.
Question: Why detergents are preferred over soaps?
Answer: Detergents are preferred over soaps because they are more effective in removing dirt, grease, and other stains. Detergents are also more effective at low temperatures, while soaps are less effective. Detergents are also less prone to forming scum on fabric or surfaces, and they often contain fewer harsh chemicals than soaps.
Give the electronic configuration of group 16 elements.
Answer: The group 16 elements of the periodic table are oxygen, sulfur, selenium, tellurium, and polonium.
The electronic configuration of each element is as follows:
Oxygen: [He] 2s2 2p4
Sulfur: [Ne] 3s2 3p4
Selenium: [Ar] 3d10 4s2 4p4
Tellurium: [Kr] 4d10 5s2 5p4
Polonium: [Xe] 4f14 5d10 6s2 6p4
Chemistry: Solved Previous Year’s Question Paper for NCERT/CBSE Class12th Read More »
Question: How is activation Energy affected by the rise in temperature?
Answer: As temperature rises, activation energy is lowered. This means that reactions will occur faster as temperature increases, as less energy is required to initiate the reaction.
Question: Why are artificial sweetening agents needed? Give two examples
Answer: Artificial sweetening agents are needed because they provide a sweet taste to food and beverages without the added calories or health risks associated with consuming large amounts of sugar. Examples include aspartame and sucralose.
