List of top Questions asked in CBSE CLASS XII

Assertion (A): In a first order reaction, if the concentration of the reactant is doubled, its half-life is also doubled. Reason (R): The half-life of a reaction does not depend upon the initial concentration of the reactant in a first order reaction.

Assertion (A): Vitamin D cannot be stored in our body. Reason (R): Vitamin D is fat-soluble vitamin and is not excreted from the body in urine.

Assertion (A): Aromatic primary amines cannot be prepared by Gabriel Phthalimide synthesis. Reason (R): Aryl halides do not undergo nucleophilic substitution reaction with the anion formed by phthalimide.

The elements of 3d transition series are given as: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn
Answer the following:

Read the passage carefully and answer the questions that follow.
Passage: The rate of a chemical reaction is expressed either in terms of decrease in the concentration of reactants or increase in the concentration of a product per unit time. Rate of the reaction depends upon the nature of reactants, concentration of reactants, temperature, presence of catalyst, surface area of the reactants and presence of light. Rate of reaction is directly related to the concentration of reactant. Rate law states that the rate of reaction depends upon the concentration terms on which the rate of reaction actually depends, as observed experimentally. The sum of powers of the concentration of the reactants in the Rate law expression is called order of reaction while the number of reacting species taking part in an elementary reaction which must collide simultaneously in order to bring about a chemical reaction is called molecularity of the reaction.
 Answer the following questions:

Phenols undergo electrophilic substitution reactions readily due to the strong activating effect of the OH group attached to the benzene ring. Since the OH group increases the electron density more to the ortho- and para- positions, one of the examples of the aldehyde group being introduced on the aromatic ring of phenol, ortho to the hydroxyl group. This is a general method used for the ortho-formylation of phenols.
Answer the following questions:

Aarti prepared a fixture of 11 teams to conduct the Kho-Kho tournament in her locality as shown below:

Tarun’s physical education teacher gave him the responsibility of organizing a Kabaddi competition in school. Tarun along with his classmates formed several committees and prepared a knockout fixture of 17 teams for the Kabaddi tournament. He faced many challenges in organizing the match, but finally, he was successful.
Answer the following questions based on the above case and your prior knowledge:

During the Physical Education class, Vivek’s physical education teacher provided information about sports for children with special needs. He explained how they are catered for the Paralympics, Deaflympics and Special Olympics. Additionally, he advised them to motivate such children to participate in physical activities to improve their performance.
Answer the following questions based on the above case and your prior knowledge:

Diya went to a sports training center for the first time. Her coach informed her that participation in sports not only promotes physical growth but also has social and psychological benefits. He highlighted numerous physical benefits for muscles, heart, and respiratory systems. He advised her to continue daily practice to improve her health-related and skill-related fitness.
Answer the following questions based on the above case and your prior knowledge:

Royal Glaze Ltd. continues to maintain its position as one of the largest consumer goods companies in the world. Its organisational structure is designed to facilitate the achievement of its objectives in alignment with its vision statement. The company maintains two distinct product divisions in its organisational structure- ’Foods’ and ’Home Care’. Looking ahead, the company is focusing on embracing changes so that it can continue to be the market leader. As part of its expansion plans, it is planning to venture into the electronics segment in the near future.

State any four points of importance of the controlling function of management.

Complete the following table. Construct/Express the Consumption function at ₹ 200 crore level of income. \[ \begin{array}{|c|c|c|c|} \hline \textbf{Income (Y)} & \textbf{Savings (S)} & \textbf{Average Propensity to Consume (APC)} & \textbf{Marginal Propensity to Save (MPS)} \\ \hline 0 & -30 & 1 & 0.2 \\ 100 & 20 & 0.85 & 0.2 \\ 200 & 70 & 0.85 & 0.2 \\ 300 & 120 & 0.8 & 0.2 \\ \hline \end{array} \]

Addiction to mobile phones is becoming a cause of concern today. It is impacting both physical and mental health of young and old alike. You attended a workshop on ‘Joy of Missing Out’ organized by Home Association. As the local correspondent, write a report on the event. You may use the following cues along with your own ideas. You are Rita/Rakesh of Savitri Nagar.

Stephen Spender’s visit to the Gemini Studios was viewed as an unexplained mystery by the Gemini family. How did Asokamitran solve this mystery years later? (Poets and Pancakes)

There was an “Each One Teach One” camp held in your school during summer vacations. As student editor of the school magazine, write a report on the camp. You are Sneh/Surbhi. You may use the following cues along with your ideas to write the report. Invent necessary details. \begin{center} \fbox{ \parbox{0.9\linewidth}{ Cues: Children from neighbourhood slums — 5 to 8 years Student volunteers from class XI Foundational numeracy and literacy skills Distribution of stationery and books Both oral and written approaches General knowledge quizzes Certificates given } } \end{center}