请帮我生成关于马来西亚Form 3 KSSM thermochemistry 得内容介绍 exothermic and endothermic

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Thermochemistry is the study of energy changes in chemical reactions. Chemical reactions can be classified into two main types: exothermic and endothermic reactions. Exothermic reactions release heat energy to the surroundings, causing the temperature of the environment to increase. Endothermic reactions absorb heat energy from the surroundings, causing the temperature of the environment to decrease. Exothermic reactions are characterized by the release of heat energy to the surroundings. In these reactions, the temperature of the surroundings increases because energy is given out during the reaction. The enthalpy change, delta H, is negative, indicating that energy is released. Common examples include combustion reactions like burning fuel, neutralization reactions between acids and bases, and cellular respiration in living organisms. Endothermic reactions are characterized by the absorption of heat energy from the surroundings. In these reactions, the temperature of the surroundings decreases because energy is taken in during the reaction. The enthalpy change, delta H, is positive, indicating that energy is absorbed. Common examples include photosynthesis in plants, thermal decomposition reactions, and physical changes like melting ice. Enthalpy change, represented by delta H, is the heat energy change during a chemical reaction at constant pressure. It is calculated as the difference between the enthalpy of products and reactants. When delta H is negative, the reaction is exothermic, meaning heat is released. When delta H is positive, the reaction is endothermic, meaning heat is absorbed. This concept is fundamental in understanding energy changes in chemical reactions. Thermochemistry has many practical applications in daily life and industry. Hand warmers use exothermic reactions to generate heat, while instant ice packs use endothermic reactions to absorb heat and provide cooling. Understanding these principles helps in designing energy-efficient processes, implementing safety measures, and optimizing industrial reactions. This knowledge is essential for students studying chemistry as it connects theoretical concepts with real-world applications. 放热反应的特征是向周围环境释放热能。在这些反应中，周围环境的温度会升高，因为反应过程中能量被释放出来。焓变ΔH为负值，表示能量被释放。常见的例子包括燃烧反应如燃料燃烧、酸碱中和反应，以及生物体内的呼吸作用。 吸热反应的特征是从周围环境吸收热能。在这些反应中，周围环境的温度会降低，因为反应过程中需要吸收能量。焓变ΔH为正值，表示能量被吸收。常见的例子包括植物的光合作用、热分解反应，以及物理变化如冰的融化。 焓变用ΔH表示，是化学反应在恒压条件下的热能变化。它的计算公式是生成物的焓减去反应物的焓。当ΔH为负值时，反应是放热的，意味着热量被释放。当ΔH为正值时，反应是吸热的，意味着热量被吸收。这个概念是理解化学反应中能量变化的基础。 热化学在日常生活和工业中有许多实际应用。暖手袋利用放热反应产生热量，而即时冰袋利用吸热反应吸收热量提供冷却效果。理解这些原理有助于设计节能过程、实施安全措施和优化工业反应。这些知识对学习化学的学生来说非常重要，因为它将理论概念与实际应用联系起来。