valence electron

简明释义

价电子

英英释义

例句

1.In the periodic table, elements in the same group have the same number of valence electrons.

在周期表中，同一组的元素具有相同数量的价电子。

2.To form a stable molecule, atoms often share or transfer their valence electrons.

为了形成稳定的分子，原子通常会共享或转移它们的价电子。

3.The number of valence electrons determines how an atom will bond with others.

原子的价电子数量决定了它与其他原子的结合方式。

4.Sodium has one valence electron, which makes it highly reactive.

钠有一个价电子，这使得它具有很强的反应性。

5.The octet rule states that atoms tend to gain, lose, or share valence electrons to achieve a full outer shell.

八隅规则指出，原子倾向于获得、失去或共享价电子以达到完整的外壳。

作文

Understanding the concept of valence electron is essential for grasping the fundamentals of chemistry and how elements interact with each other. A valence electron is defined as an electron that is located in the outermost shell of an atom and can participate in the formation of chemical bonds. These electrons play a crucial role in determining the chemical properties of an element, influencing how it reacts with other elements and compounds. To illustrate the importance of valence electrons, consider the example of sodium (Na) and chlorine (Cl). Sodium has one valence electron in its outer shell, while chlorine has seven. When these two elements react, sodium donates its single valence electron to chlorine, resulting in the formation of sodium chloride (NaCl), or table salt. This transfer of electrons is a classic example of ionic bonding, where one atom loses electrons and another gains them, leading to the creation of charged ions that attract each other.The number of valence electrons in an element is determined by its position on the periodic table. Elements in the same group or column typically have the same number of valence electrons. For instance, all alkali metals, which are found in Group 1 of the periodic table, have one valence electron. This commonality results in similar reactivity patterns among these elements, as they all tend to lose their single valence electron during chemical reactions, forming positive ions.In contrast, the noble gases, located in Group 18, have a complete set of eight valence electrons (except for helium, which has two). This full outer shell configuration makes noble gases very stable and unreactive. The stability provided by having a complete octet of valence electrons explains why these gases do not readily form compounds with other elements.Understanding valence electrons also aids in predicting molecular shapes and bonding types. For example, in covalent bonding, atoms share valence electrons to achieve stability. The sharing arrangement can lead to different molecular geometries, depending on how many valence electrons are involved and the specific atoms involved in the bond. The VSEPR (Valence Shell Electron Pair Repulsion) theory is a model used to predict the geometry of molecules based on the repulsion between valence electrons.In summary, valence electrons are fundamental to understanding chemical bonding and the behavior of elements. They determine how atoms interact, whether through the transfer of electrons in ionic bonds or the sharing of electrons in covalent bonds. By studying valence electrons, we can unlock the mysteries of chemical reactions and the formation of new substances, making this concept a cornerstone of chemistry education and research. Without a solid grasp of valence electrons, one cannot fully appreciate the complexity and beauty of the chemical world around us.

理解价电子的概念对于掌握化学的基本原理以及元素之间的相互作用至关重要。价电子被定义为位于原子最外层壳层中的电子，并且可以参与化学键的形成。这些电子在决定元素的化学性质方面发挥着至关重要的作用，影响着元素与其他元素和化合物的反应方式。为了说明价电子的重要性，可以考虑钠（Na）和氯（Cl）的例子。钠在其最外层中具有一个价电子，而氯则有七个。当这两个元素反应时，钠将其唯一的价电子捐赠给氯，从而形成氯化钠（NaCl），即食盐。这种电子的转移是离子键的经典例子，其中一个原子失去电子而另一个原子获得电子，导致带电离子的形成，这些离子相互吸引。元素中价电子的数量由其在周期表中的位置决定。同一组或列中的元素通常具有相同数量的价电子。例如，所有碱金属都位于周期表的第1组，具有一个价电子。这种共同性导致这些元素之间的反应模式相似，因为它们都倾向于在化学反应中失去其单个的价电子，形成正离子。相比之下，位于第18组的惰性气体具有完整的八个价电子（氦除外，氦有两个）。这种完整的外壳配置使得惰性气体非常稳定且不活泼。拥有完整的价电子八重态所提供的稳定性解释了为什么这些气体不容易与其他元素形成化合物。理解价电子还有助于预测分子形状和键类型。例如，在共价键中，原子共享价电子以实现稳定。共享的排列可能导致不同的分子几何形状，具体取决于涉及的价电子的数量和参与键合的特定原子。VSEPR（价壳电子对排斥）理论是一种用于预测分子几何形状的模型，基于价电子之间的排斥。总之，价电子是理解化学键和元素行为的基础。它们决定了原子如何相互作用，无论是通过在离子键中转移电子，还是在共价键中共享电子。通过研究价电子，我们可以揭开化学反应和新物质形成的奥秘，使这一概念成为化学教育和研究的基石。如果没有对价电子的深入理解，就无法充分欣赏我们周围化学世界的复杂性和美丽。