lone pair

简明释义

非共有电子对

英英释义

例句

1.In the Lewis structure of ethanol, the oxygen has two bonds and two lone pairs.

在乙醇的路易斯结构中，氧有两个键和两个孤对电子。

2.The presence of a lone pair on the nitrogen atom affects the geometry of ammonia.

氮原子上的孤对电子的存在影响了氨的几何形状。

3.The lone pair on the sulfur atom in H2S causes the molecule to have a bent shape.

H2S中硫原子的孤对电子使得分子呈弯曲形状。

4.In the molecular structure of water, the oxygen atom has two hydrogen atoms bonded to it and one lone pair of electrons.

在水的分子结构中，氧原子与两个氢原子相连，并有一对孤对电子。

5.Carbon dioxide is linear because there are no lone pairs on the central carbon atom.

二氧化碳是线性的，因为中心碳原子上没有孤对电子。

作文

In the fascinating world of chemistry, understanding molecular structures is crucial for grasping how different substances interact with one another. One essential concept in this realm is the idea of a lone pair, which refers to a pair of valence electrons that are not shared with another atom. These electrons play a significant role in determining the shape and reactivity of molecules. For instance, in water (H2O), the oxygen atom has two lone pairs of electrons. This arrangement not only affects the bond angles between the hydrogen atoms but also influences the overall polarity of the molecule. The presence of lone pairs can lead to unique properties, making water an excellent solvent for many substances.The concept of lone pairs extends beyond just water. In ammonia (NH3), the nitrogen atom has one lone pair of electrons, which results in a trigonal pyramidal shape. This geometry is crucial for understanding how ammonia interacts with other molecules, such as when it acts as a base in chemical reactions. The lone pair allows ammonia to donate electrons, facilitating the formation of new bonds.Moreover, lone pairs can significantly influence the acidity and basicity of compounds. For example, in carboxylic acids, the lone pairs on the oxygen atoms can stabilize negative charges when the acid donates a proton (H+). This stabilization is vital for understanding the behavior of acids in various chemical environments. Similarly, in organic chemistry, the presence of lone pairs can dictate the reactivity patterns of functional groups, guiding chemists in predicting the outcomes of reactions.In addition to their role in chemical reactivity, lone pairs also contribute to the physical properties of substances. For instance, the presence of lone pairs can affect boiling and melting points. Molecules with significant lone pairs often exhibit stronger intermolecular forces, such as hydrogen bonding, leading to higher boiling points compared to similar molecules without lone pairs. This phenomenon is evident when comparing water to methane (CH4); water's ability to form hydrogen bonds due to its lone pairs results in a much higher boiling point.In conclusion, the concept of a lone pair is fundamental in the study of chemistry. It helps explain the molecular geometry, reactivity, and physical properties of various substances. By recognizing the importance of lone pairs, students and professionals alike can gain a deeper understanding of chemical interactions and the behavior of different compounds. As we continue to explore the intricate details of molecular structures, the role of lone pairs will undoubtedly remain a key topic of interest in the field of chemistry.

在化学的迷人世界中，理解分子结构对于掌握不同物质之间的相互作用至关重要。一个基本概念是孤对电子的概念，它指的是一对不与其他原子共享的价电子。这些电子在决定分子的形状和反应性方面发挥着重要作用。例如，在水（H2O）中，氧原子有两个孤对电子。这种排列不仅影响氢原子之间的键角，还影响分子的整体极性。孤对电子的存在可以导致独特的性质，使水成为许多物质的优秀溶剂。孤对电子的概念不仅限于水。在氨（NH3）中，氮原子有一个孤对电子，这使得其呈现三角锥形状。这种几何形状对于理解氨如何与其他分子相互作用至关重要，例如当它在化学反应中作为碱时。孤对电子使氨能够捐赠电子，促进新键的形成。此外，孤对电子在化合物的酸碱性方面也会产生显著影响。例如，在羧酸中，氧原子上的孤对电子可以稳定酸捐赠质子（H+）时产生的负电荷。这种稳定性对于理解酸在各种化学环境中的行为至关重要。同样，在有机化学中，孤对电子的存在可以决定官能团的反应模式，引导化学家预测反应的结果。除了在化学反应性中的作用外，孤对电子还会影响物质的物理性质。例如，孤对电子的存在可以影响沸点和熔点。具有显著孤对电子的分子往往表现出更强的分子间作用力，如氢键，从而导致比没有孤对电子的类似分子具有更高的沸点。这种现象在比较水和甲烷（CH4）时尤为明显；由于水的孤对电子能够形成氢键，导致其沸点远高于甲烷。总之，孤对电子的概念在化学研究中是基础性的。它帮助解释了各种物质的分子几何、反应性和物理性质。通过认识到孤对电子的重要性，学生和专业人士都可以更深入地理解化学相互作用和不同化合物的行为。随着我们继续探索分子结构的复杂细节，孤对电子的作用无疑将在化学领域中保持一个重要的研究主题。