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Ques 9: What does one mean by exothermic and endothermic reactions? Give examples.   Ans 9: Chemical reactions that release energy in the form of heat, light, or sound are called  exothermic reactions. Example: Mixture of sodium and chlorine to yield table salt.                2 Na + Cl 2  →2 Na Cl In other words, combination reactions are exothermic.  Reactions that require energy or absorb   energy in order to proceed are called endothermic reactions.  For example: In the process of photosynthesis, plants use the energy from the sun to convert carbon dioxide and water to glucose and oxygen .       6  CO 2  + 6  H 2 O  →  C 6 H 12 O 6  + 6  O 2 «« Previous question              Next question »»

Ques 1: A Mendelian experiment consisted of breeding tall pea(matar) plants bearing violet flowers with short pea plants bearing white flowers. The progeny of all bore violet flowers, but almost half  of them were short. This suggests that the genetic make-up of the tall parent can be depicted as   (a) TTWW (b) TTww (c) TtWW (d) TtWw Ans 1: (c) The genetical make-up of the tall parent can be depicted as TtWW .  Since all the progeny of pea plant bore violet flowers, it means that all the tall plants are having violet flowers has W W genotype for violet flower colour.   Since the progeny is both tall tall and short, the parent plant was not a pure tall plant. Its genotype must be T t.   Therefore, the cross involved in the given in the question is                        TtWw × ttww                            ...

                          Data Mining Need for Data Mining Data mining is the process of extracting meaningful patterns, trends, and knowledge from large datasets. Its need arises from: Data Explosion : Organizations generate massive amounts of data that need to be analyzed effectively. Decision-Making : It supports informed decision-making by identifying hidden patterns and correlations. Competitive Advantage : Helps businesses optimize processes, enhance customer relationships, and forecast trends. Automation : Reduces manual data analysis efforts and increases efficiency. Problem-Solving : Detects anomalies, predicts outcomes, and aids in problem-solving across domains. Data Mining Tasks Classification : Assigning items to predefined categories (e.g., spam email detection). Clustering : Grouping similar data points together without predefined labels (e.g., customer segmentation). Regression : Predicting ...

Ques : 2.0 gram of a metal burst in oxygen give 3.2 gram of its oxide. 1.42 gram of the same metal heat in steam give 2.27 gram of its oxide which toys shown by this data?  Ans : In the first compound, 3.2 gram of metal oxide contained 2.0 gram of metal 100 gram of metal oxide contained metal =2.0/3.2 × 100= 62.5 g :· % metal in first compound= 62.5% In the second compound, 2.27 gram of metal oxide contains metal = 1.42 gram 100 gram of metal oxide contains the metal= 1.42/2.27×100=62.55 gram :· % metal in first compound= 62.55% Thus, the percentage of metal in metal oxide obtained from to experiment is nearly same. Hence, the above data illustrate the law of constant composition.  <<   Previous                                                       Next   >>

Carbohydrates Carbohydrates are organic compounds composed of carbon, hydrogen, and oxygen, typically with a hydrogen-to-oxygen ratio of 2:1. They are one of the primary macronutrients and serve as a significant energy source for living organisms. They also play vital roles in the structure and function of cells. Sources of Carbohydrates Natural Sources: Plants: Grains (wheat, rice, maize), fruits (bananas, apples, mangoes), vegetables (potatoes, carrots), and legumes (lentils, beans). Dairy Products: Milk, yogurt. Sugars: Honey, sugarcane, and fruits. Processed Foods: Bread, pasta, cookies, and other carbohydrate-rich snacks. Functions of Carbohydrates Energy Source: Provide 4 kcal of energy per gram. Protein Sparing: Spare proteins from being used as energy sources. Structural Role: Form structural components like cellulose in plants. Storage: Serve as storage forms of energy (e.g., glycogen in animals and starch in plants). Sweetening Agents: Many ca...