pure substance

简明释义

纯物质

英英释义

例句

1.Water is often considered a pure substance because it consists of only H2O molecules.

水通常被认为是一种纯物质，因为它只由H2O分子组成。

2.A pure substance has distinct physical and chemical properties that can be used for identification.

纯物质具有独特的物理和化学性质，可用于鉴别。

3.Sodium chloride is a pure substance that can be obtained by evaporating seawater.

氯化钠是一种纯物质，可以通过蒸发海水获得。

4.In chemistry, a pure substance is defined as a material with a consistent composition.

在化学中，纯物质被定义为成分一致的材料。

5.Gold is an example of a pure substance since it has a uniform composition throughout.

黄金是一个纯物质的例子，因为它的成分在整个过程中都是一致的。

作文

In the world of chemistry, understanding the concept of a pure substance is fundamental. A pure substance refers to a material that has a constant composition and distinct chemical properties. This means that no matter where you obtain this substance, it will always have the same characteristics and will not contain any other substances mixed in. For instance, distilled water is considered a pure substance because it consists solely of H2O molecules without any impurities or additional compounds. On the other hand, mixtures, such as saltwater or air, are not pure substances because they contain two or more different components that can vary in proportion. The distinction between pure substances and mixtures is crucial in various fields, including medicine, environmental science, and engineering. In medicine, for example, the purity of drugs is critical; a pure substance ensures that patients receive the correct dosage without harmful additives or contaminants. In addition to being important in practical applications, the study of pure substances also provides insight into the nature of matter. Scientists categorize pure substances into two main types: elements and compounds. Elements are substances that cannot be broken down into simpler substances by chemical means, such as oxygen (O) or gold (Au). Compounds, on the other hand, consist of two or more elements that are chemically combined in fixed ratios, like water (H2O) or carbon dioxide (CO2). Both categories of pure substances exhibit unique properties that differ from those of their component elements.The identification and analysis of pure substances are achieved through various techniques in the laboratory. Techniques such as chromatography, spectroscopy, and mass spectrometry allow chemists to determine the purity of a substance and identify its components. These methods are vital for research and quality control in industries ranging from pharmaceuticals to food production. For example, ensuring that a food product is free from contaminants requires rigorous testing to confirm that it is a pure substance or meets specific purity standards.Understanding pure substances also plays a significant role in environmental science. For example, assessing the purity of water sources is essential for public health. Contaminated water may contain various substances that can pose risks to human health. Therefore, identifying whether water is a pure substance or a mixture with pollutants is crucial for developing treatment processes and ensuring safe drinking water.In conclusion, the concept of a pure substance is vital across multiple disciplines. From its definition as a material with a constant composition to its implications in medicine, environmental science, and industrial applications, the significance of pure substances cannot be overstated. As we continue to explore the complexities of matter, the understanding of pure substances will remain a cornerstone of scientific inquiry and practical application.

在化学世界中，理解“纯物质”的概念是基础。纯物质指的是一种具有恒定成分和独特化学性质的材料。这意味着无论你从哪里获得这种物质，它总会具有相同的特性，并且不会含有任何其他混合的物质。例如，蒸馏水被认为是一种纯物质，因为它仅由H2O分子组成，没有任何杂质或额外的化合物。另一方面，像盐水或空气这样的混合物就不是纯物质，因为它们包含两种或更多不同的成分，且这些成分的比例可以变化。纯物质和混合物之间的区别在医学、环境科学和工程等多个领域至关重要。在医学中，例如，药物的纯度至关重要；纯物质确保患者接受正确剂量，而没有有害的添加剂或污染物。除了在实际应用中的重要性，研究纯物质也提供了对物质本质的洞察。科学家将纯物质分为两种主要类型：元素和化合物。元素是指无法通过化学方法分解成更简单物质的物质，如氧（O）或金（Au）。而化合物则由两种或更多元素以固定比例化学结合而成，比如水（H2O）或二氧化碳（CO2）。这两类纯物质展现出独特的性质，这些性质与其组成元素不同。在实验室中，通过各种技术来识别和分析纯物质。色谱法、光谱法和质谱法等技术使化学家能够确定物质的纯度并识别其成分。这些方法对于制药、食品生产等行业的研究和质量控制至关重要。例如，确保食品产品不含污染物需要严格测试，以确认其是否为纯物质或符合特定的纯度标准。理解纯物质在环境科学中也发挥着重要作用。例如，评估水源的纯度对公共健康至关重要。受污染的水可能含有多种物质，这些物质可能对人类健康构成风险。因此，识别水是否为纯物质或含有污染物的混合物，对于开发处理过程和确保安全饮用水至关重要。总之，纯物质的概念在多个学科中都是至关重要的。从其作为具有恒定成分的材料的定义，到其在医学、环境科学和工业应用中的影响，纯物质的重要性不容小觑。随着我们继续探索物质的复杂性，对纯物质的理解将始终是科学研究和实际应用的基石。