atomic mass unit

简明释义

原子质量单位

英英释义

例句

1.The mass of a proton is approximately 1 atomic mass unit, which is equivalent to about 1.67 × 10^-27 kg.

质子的质量约为1原子质量单位，相当于约1.67 × 10^-27千克。

2.In chemistry, the atomic mass unit is used to express the masses of atoms and molecules.

在化学中，原子质量单位用于表示原子和分子的质量。

3.When calculating molecular weights, chemists often refer to the atomic mass unit for accuracy.

在计算分子量时，化学家通常参考原子质量单位以确保准确性。

4.Carbon-12 is defined as having a mass of exactly 12 atomic mass units.

碳-12被定义为质量恰好为12原子质量单位。

5.The atomic mass unit allows scientists to compare the mass of different isotopes easily.

原子质量单位使科学家能够轻松比较不同同位素的质量。

作文

The concept of an atomic mass unit is fundamental in the field of chemistry and physics. It provides a standard way to express the mass of atomic and molecular particles, allowing scientists to communicate and compare their findings effectively. An atomic mass unit (often abbreviated as amu) is defined as one twelfth the mass of a carbon-12 atom, which serves as a reference point for measuring the mass of other atoms. This unit is crucial because atoms are incredibly small, and using grams or kilograms would result in unwieldy numbers that are difficult to work with.Understanding the atomic mass unit helps students and researchers grasp the relative sizes and weights of different elements. For instance, hydrogen, the lightest element, has an atomic mass of approximately 1 amu, while heavier elements like gold have an atomic mass of about 197 amu. This scale allows chemists to predict how elements will interact based on their masses and to calculate the amounts needed for various reactions.In practical applications, the atomic mass unit plays a significant role in stoichiometry, the branch of chemistry that deals with the quantitative relationships between reactants and products in chemical reactions. By knowing the atomic masses of the elements involved, chemists can determine how much of each substance is required to produce a desired amount of product. This is especially important in industries such as pharmaceuticals, where precise measurements are critical for creating effective medications.Additionally, the atomic mass unit is essential in nuclear chemistry and physics. In these fields, understanding the masses of subatomic particles—such as protons, neutrons, and electrons—is vital for studying atomic structure and nuclear reactions. For example, a proton has a mass of approximately 1.007 amu, while a neutron is about 1.008 amu. The slight differences in mass between these particles are important when calculating binding energies and understanding how atoms combine to form molecules.Moreover, the atomic mass unit is not only limited to individual atoms but also extends to molecules. When calculating the molecular weight of compounds, chemists sum the atomic masses of all the atoms in a molecule, expressed in atomic mass units. This information is crucial for determining the properties of substances, such as their boiling points, melting points, and solubility. For instance, water (H2O) has a molecular weight of about 18 amu, which influences its behavior in various chemical reactions.In conclusion, the atomic mass unit is a vital concept in science that facilitates communication and understanding in chemistry and physics. It allows for the accurate measurement of atomic and molecular masses, enabling scientists to make predictions and calculations essential for research and industry. As we continue to explore the intricacies of atomic interactions and chemical reactions, the significance of the atomic mass unit remains ever-present, underscoring its importance in our understanding of the natural world.

“原子质量单位”这一概念在化学和物理学领域中是基础性的。它提供了一种标准方式来表达原子和分子粒子的质量，使科学家能够有效地交流和比较他们的发现。“原子质量单位”（通常缩写为amu）被定义为碳-12原子质量的十二分之一，这一基准点用于测量其他原子的质量。这个单位至关重要，因为原子极其微小，使用克或千克会导致难以处理的庞大数字。理解“原子质量单位”有助于学生和研究人员掌握不同元素的相对大小和重量。例如，氢是最轻的元素，其原子质量约为1 amu，而较重的元素如金的原子质量约为197 amu。这一尺度使化学家能够根据元素的质量预测它们的相互作用，并计算各种反应所需的量。在实际应用中，“原子质量单位”在化学计量学中发挥着重要作用，这是化学的一个分支，涉及化学反应中反应物和产品之间的定量关系。通过了解参与元素的原子质量，化学家可以确定每种物质所需的精确量，以产生所需的产品。在制药等行业中，这一点尤其重要，因为精确的测量对于创造有效的药物至关重要。此外，“原子质量单位”在核化学和物理学中也至关重要。在这些领域，理解亚原子粒子的质量，例如质子、中子和电子，对于研究原子结构和核反应至关重要。例如，质子的质量约为1.007 amu，而中子的质量约为1.008 amu。这些粒子之间的微小质量差异在计算结合能和理解原子如何结合形成分子时非常重要。此外，“原子质量单位”不仅限于单个原子，还扩展到分子。当计算化合物的分子量时，化学家将分子中所有原子的原子质量相加，以“原子质量单位”表示。这些信息对于确定物质的性质至关重要，例如它们的沸点、熔点和溶解度。例如，水（H2O）的分子量约为18 amu，这影响其在各种化学反应中的行为。总之，“原子质量单位”是科学中的一个重要概念，促进了化学和物理学中的交流和理解。它允许对原子和分子质量进行准确测量，使科学家能够进行预测和计算，这对于研究和工业至关重要。随着我们继续探索原子相互作用和化学反应的复杂性，“原子质量单位”的重要性始终存在，强调了它在我们理解自然世界中的重要性。