covalent bond

简明释义

共价键

英英释义

例句

1.In diamond, each carbon atom forms four covalent bonds (共价键) with other carbon atoms.

在钻石中，每个碳原子与其他碳原子形成四个共价键 (共价键)。

2.When two nonmetals react, they typically form a covalent bond (共价键).

当两个非金属反应时，它们通常会形成一个共价键 (共价键)。

3.The covalent bonds (共价键) in organic molecules are essential for biological functions.

有机分子中的共价键 (共价键) 对生物功能是至关重要的。

4.The strength of a covalent bond (共价键) can vary depending on the atoms involved.

一个共价键 (共价键) 的强度可以根据参与的原子而有所不同。

5.In a water molecule, the hydrogen atoms are held together by a covalent bond (共价键) with the oxygen atom.

在水分子中，氢原子与氧原子通过一个共价键 (共价键) 结合在一起。

作文

In the world of chemistry, understanding the fundamental forces that hold atoms together is essential for grasping how molecules are formed and how they interact. One of the most important types of chemical bonds is the covalent bond, which plays a crucial role in the structure and function of countless substances. A covalent bond occurs when two atoms share one or more pairs of electrons, allowing them to achieve a more stable electronic configuration. This sharing of electrons is particularly common among nonmetals, which tend to have similar electronegativities, meaning they have a comparable ability to attract electrons.The concept of a covalent bond can be illustrated through the example of water (H₂O). In a water molecule, each hydrogen atom shares its single electron with the oxygen atom, which has six electrons in its outer shell. By sharing these electrons, both hydrogen and oxygen can achieve a full outer shell, leading to a stable configuration. This simple yet profound interaction exemplifies how covalent bonds form the backbone of molecular structures, influencing not only the physical properties of substances but also their chemical reactivity.Another interesting aspect of covalent bonds is their variability. Depending on the number of shared electron pairs, we can categorize covalent bonds into single, double, and triple bonds. A single bond involves one pair of shared electrons, while a double bond involves two pairs, and a triple bond consists of three pairs. These variations significantly affect the strength and length of the bonds. For instance, a double bond is generally stronger and shorter than a single bond, which is critical for the stability of larger molecules.Moreover, the presence of covalent bonds in organic compounds is what makes life possible. Proteins, carbohydrates, lipids, and nucleic acids are all composed of molecules held together by covalent bonds. The specific arrangements of these bonds dictate the unique properties and functions of biological macromolecules. For example, the sequence of amino acids in a protein is determined by the covalent bonds that link them together, which ultimately influences the protein's shape and function in biological processes.In addition to their significance in organic chemistry, covalent bonds are also vital in inorganic chemistry. Many minerals and materials, such as diamonds and graphite, exhibit unique properties due to the arrangement and type of covalent bonds present in their structures. Diamonds, for example, have a three-dimensional network of covalent bonds that gives them exceptional hardness, while graphite's layered structure allows it to conduct electricity.In conclusion, the covalent bond is a fundamental concept in chemistry that provides insight into the behavior of atoms and molecules. By sharing electrons, atoms can achieve stability and form the diverse array of substances that make up our world. Whether in the context of biological systems or inorganic materials, understanding covalent bonds is crucial for anyone looking to delve deeper into the sciences. As we continue to explore the intricate relationships between atoms and molecules, the importance of covalent bonds will undoubtedly remain a central theme in our quest for knowledge.

在化学世界中，理解将原子结合在一起的基本力对于掌握分子的形成及其相互作用至关重要。其中最重要的化学键之一是共价键，它在无数物质的结构和功能中发挥着关键作用。共价键发生在两个原子共享一对或多对电子时，从而使它们能够达到更稳定的电子配置。这种电子共享在非金属之间尤其常见，因为它们的电负性相似，意味着它们吸引电子的能力相当。共价键的概念可以通过水（H₂O）的例子来说明。在水分子中，每个氢原子与氧原子共享其单个电子，而氧原子在外壳中有六个电子。通过共享这些电子，氢和氧都可以实现完整的外壳，从而导致稳定的配置。这种简单而深刻的相互作用示范了共价键如何构成分子结构的基础，影响物质的物理属性以及它们的化学反应性。共价键的另一个有趣方面是它们的可变性。根据共享电子对的数量，我们可以将共价键分为单键、双键和三键。单键涉及一对共享电子，而双键涉及两对，三键则由三对组成。这些变化显著影响键的强度和长度。例如，双键通常比单键更强且更短，这对较大分子的稳定性至关重要。此外，共价键在有机化合物中的存在使生命成为可能。蛋白质、碳水化合物、脂类和核酸都是由通过共价键连接在一起的分子组成的。这些键的特定排列决定了生物大分子的独特性质和功能。例如，蛋白质中氨基酸的序列由连接它们的共价键决定，这最终影响了蛋白质在生物过程中的形状和功能。除了在有机化学中的重要性，共价键在无机化学中也至关重要。许多矿物和材料，如钻石和石墨，由于其结构中存在的共价键的排列和类型而表现出独特的属性。例如，钻石具有三维网络的共价键，使其具有卓越的硬度，而石墨的层状结构则使其能够导电。总之，共价键是化学中的一个基本概念，为我们提供了关于原子和分子行为的深入见解。通过共享电子，原子可以实现稳定性并形成构成我们世界的多样化物质。无论是在生物系统还是无机材料的背景下，理解共价键对任何希望深入研究科学的人来说都是至关重要的。随着我们继续探索原子和分子之间的复杂关系，共价键的重要性无疑将始终是我们追求知识的核心主题。