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  • 同位素与核稳定

    Atomic Structure With Protons, Neutrons, And Electron Clouds.

    The nuclei of atoms contain protons and neutrons while electron clouds surrounding the nuclei contain  the electrons . The positively charged protons are very close together in an atomic nucleus and the repulsive force of the like charges is tremendous. The strong force is a type of interaction that binds together protons and neutrons. Without the strong force, the positively charged protons would blow the nucleus apart.
    ::原子核心包含质子和中子,而核心周围的电子云则包含电子。正电荷质子在原子核中非常接近,类似电荷的可憎力量非常巨大。强力是一种将质子和中子联系在一起的相互作用。没有强力,正电荷质子就会将核分开。

    Isotopes
    ::离线( I)

    Until 1932, the positively charged nucleus  of an atom was known to exist, but it was believed to contain only protons. The nucleus was known to be surrounded by enough negatively charged electrons to make the atom electrically neutral . Most of the atom was empty space, with its mass concentrated in the tiny nucleus.
    ::直到1932年,一个原子的正电荷核一直存在,但据信它只含有质子。 据知这个核被足够负电荷电子包围,使得原子的电能中和。 大部分原子是空的,其质量集中在小核中。

    Twelve years earlier, Lord Ernest Rutherford, a pioneer in atomic structure, had postulated the existence of a third, neutral, sub-atomic particle, with the approximate mass of a proton, that could result from the capture of an electron by a proton. This postulation stimulated a search for the particle. However, its electrical neutrality complicated the search because almost all experimental techniques of this period measured charged particles.
    ::十二年前,原子结构的先驱欧内斯特·卢瑟福德勋爵曾假设存在第三个中性亚原子粒子,质子的大致质量可能来自质子捕获电子的结果。这一假设刺激了对粒子的搜索。然而,其电子中性使得搜索复杂化了,因为这一时期几乎所有实验技术都测量了带电粒子。

    James Chadwick bombarded hydrogen atoms in paraffin with beryllium emissions. By comparing the energies of recoiling charged particles from different targets, he proved that the beryllium emissions contained a neutral component with a mass approximately equal to that of the proton. He called it the neutron in a paper published in 1932.
    ::James Chadwick在石蜡中的氢原子中投射了排放物。他比较了不同目标的后退带电粒子的能量,证明排放含有中性成分,其质量大约相当于质子的质量。他在1932年发表的一篇论文中将其称为中子。

    Since the identification of the neutron, the model of the atomic nucleus has changed very little. According to this model, a nucleus is considered to be an aggregate of protons and neutrons. A proton has a positive charge of  @$\begin{align*}1.6 \times 10^{-19} \ C\end{align*}@$ and a mass of @$\begin{align*}1.673 \times 10^{-27} \ kg\end{align*}@$ . The neutron is electrically neutral and has a mass of @$\begin{align*}1.675 \times 10^{-27} \ kg\end{align*}@$ . These two constituents of a nucleus are referred to collectively as nucleons.
    ::自中子识别以来,原子核的模型变化很小。 根据这个模型, 核心被视为质子和中子的总和。 质子的正电荷为 @ $\ begin{ align}} 1.6\ times 10\\\ { 19}\ C\ end{ align} $ 和质量为 @ $\ begin{ align} 1.673\ times 10\ 27}\ knd{ { align} 。 中子的中子在电子上是中性的, 质量为 @ $\ begin{ } 1.675\ timets 10\\\\\ 27}\ k\\ end{ leign\ $。 核心的这两个成分统称为核块 。 </span> </p> <button class="play-button btn btn-success" style="float: right;" value="@s"> 播放段落 </button> <p id="x-ck12-NGFhM2VkOTI0ZTcxNzYzNmFiMGQ0NjhlNjZiZTU5OGY.-mpj"> Although the hydrogen nucleus consists of a single proton, the nuclei of all other elements contain both neutrons and protons. The different types of nuclei are referred to as <strong> <span class="x-ck12-vocab-interlink" data-definition="the%20nucleus%20of%20a%20given%20isotope%20of%20an%20element%2C%20specified%20by%20its%20atomic%20number%20and%20atomic%20mass." data-id="10844" data-interlink-id="x-ck12-0um4x1v3y96fo5ts" data-json="eyJkYXRhLXBsdXJhbCI6ICJudWNsaWRlcyIsICJkYXRhLWRlZmluaXRpb24iOiAidGhlJTIwbnVjbGV1cyUyMG9mJTIwYSUyMGdpdmVuJTIwaXNvdG9wZSUyMG9mJTIwYW4lMjBlbGVtZW50JTJDJTIwc3BlY2lmaWVkJTIwYnklMjBpdHMlMjBhdG9taWMlMjBudW1iZXIlMjBhbmQlMjBhdG9taWMlMjBtYXNzLiIsICJkYXRhLWlkIjogMTA4NDQsICJkYXRhLWxhbmd1YWdlSUQiOiAxLCAiZGF0YS10ZXJtIjogIm51Y2xpZGUifQ==" data-languageid="1" data-plural="nuclides" data-term="nuclide" role="term" tabindex="0"> nuclides </span> </strong> . The number of protons in a nucleus is called the <strong> <span class="x-ck12-vocab-interlink" data-definition="number%20of%20protons%20in%20the%20nucleus%20of%20an%20atom." data-id="4942" data-interlink-id="x-ck12-23lmituj8htfeeif" data-json="eyJkYXRhLXN5bWJvbCI6ICJaIiwgImRhdGEtcGx1cmFsIjogImF0b21pYyBudW1iZXJzIiwgImRhdGEtZGVmaW5pdGlvbiI6ICJudW1iZXIlMjBvZiUyMHByb3RvbnMlMjBpbiUyMHRoZSUyMG51Y2xldXMlMjBvZiUyMGFuJTIwYXRvbS4iLCAiZGF0YS1pZCI6IDQ5NDIsICJkYXRhLWxhbmd1YWdlSUQiOiAxLCAiZGF0YS10ZXJtIjogImF0b21pYyBudW1iZXIifQ==" data-languageid="1" data-plural="atomic numbers" data-symbol="Z" data-term="atomic number" role="term" tabindex="0"> atomic number </span> </strong> and is designated by the symbol <span class="x-ck12-mathEditor" data-contenteditable="false" data-edithtml="" data-math-class="x-ck12-math" data-mathmethod="inline" data-tex="Z"> @$\begin{align*}Z\end{align*}@$ . The total number of nucleons, neutrons and protons, is designated by the symbol  @$\begin{align*}A\end{align*}@$ and is called the mass number . A nuclide with 7 protons and 8 neutrons thus has  @$\begin{align*}Z = 7\end{align*}@$ and @$\begin{align*}A = 15\end{align*}@$ . The number of neutrons, @$\begin{align*}N\end{align*}@$ , is @$\begin{align*}N = A- Z\end{align*}@$ . To specify a given nuclide, we need give only  @$\begin{align*}A\end{align*}@$ and @$\begin{align*}Z\end{align*}@$ . These can be shown in a complete nuclear symbol which takes the form
    ::虽然氢核由单个质子组成, 所有其他元素的核核包含中子和质子。 不同类型的核核被称为核核素。 核核核素的数量被称为原子编号。 由符号@$\ begin{ align}} 指定。 核核素、 中子和质子的总数由符号@$\ begin{ align}A\ end{ align}} 美元指定, 被称为质量编号。 核核素的种类包括7个质子和8个中子。 因此, 核核素的数量名为@ $\ beclide= 7\ begin{ align} = 7\\end{ align} 美元和@$\ beton_ beign=15\end{ leign} =15\end{ } 美元。 中子元的总数由符号@ be $\ begin{ be legn= a gin_ legin= a nuign_ legin} * a to we a prestime a a prestilement.

    @$$\begin{align*}^A_Z X\end{align*}@$$
    ::@ $\ begin{ ALIGIN} A @ X\ end{ ALING} $ @ $

    where  @$\begin{align*}X\end{align*}@$ is the chemical symbol for the element,  @$\begin{align*}A\end{align*}@$ is the mass number, and  @$\begin{align*}Z\end{align*}@$ is the atomic number. For example, a nitrogen nucleus containing 7 protons and 8 neutrons would be @$\begin{align*}^{15}_7 N\end{align*}@$ . Since all nitrogen atoms have 7 protons in their nucleus, sometimes the 7 is omitted and the symbol is written simply as @$\begin{align*}^{15} N\end{align*}@$ . This same nuclide is also sometimes written as nitrogen-15.
    ::@ $\ begin{ align} x\ end{ end{ align} $ 是元素的化学符号, @ $\ begin{ align}A\ end{ align} $ 是质量数, 而@$\ begin{ align}} end{ align} $ 是原子数。 例如, 包含 7 质子和 8 中子的氮核将是 @ $\ begin{ align} 15\\ 7N\ end{ align} $。 由于所有氮原子在核心中有 7 质子, 有时遗漏 7 , 符号仅写为@ $\ begin{ align} N\ end{ align} 15 。 同样的核核核有时也写为氮-15 。

    The identity of an atom is determined by the number of protons in the nucleus. All hydrogen atoms must have exactly 1 proton in the nucleus. The number of neutrons in the nuclei of atoms of a particular element, however, may vary. For example, a hydrogen atom will always have 1 proton, but may have zero, one, or two neutrons in the nucleus - as long as it has 1 proton, it is a hydrogen atom.
    ::原子的身份取决于核中质子的数量。 所有氢原子在核中必须有一个质子。 但是,特定元素原子核心中的中子数量可能有所不同。例如,氢原子总是有一个质子,但核中可能有零、一或两个中子,只要有1个质子,就是一个氢原子。

    Nuclei that have the same number of protons in the nucleus but a different number of neutrons are called isotopes . Hydrogen has three isotopes.
    ::核核中质子数量相同的核心中子数量,但不同的中子数量被称为同位素。氢有三个同位素。

    @$$\begin{align*}^1_1 \text{H} \qquad ^2_1 \text{H} \qquad ^3_1 \text{H}\end{align*}@$$
    ::@ $\ begin{ ALIGN} 1_ 1\ text{ H} \ qqquad _2_ 1\ text{ H}\ qqquad\ 3_ 1\ text{ H} { end{ leign} $

    One isotope of hydrogen has 1 proton and 0 neutrons in the nucleus so it has a mass number of 1. Another isotope of hydrogen has 1 proton and 1 neutron in the nucleus so it has a mass number of 2. The third isotope of hydrogen has 1 proton and 2 neutrons in the nucleus so it has a mass number of 3. (The isotope of hydrogen with a mass number of 2 is sometimes called deuterium and the isotope of hydrogen with a mass number of 3 is sometimes called tritium, but they are all hydrogen.) Carbon has six isotopes; carbon-11, carbon-12, carbon-13, carbon-14, carbon-15, and carbon-16. The isotopes of a given element are not all equally abundant. For example, 98.9% of all naturally occurring carbon is carbon-12 and about 1.1% is carbon-13. The other isotopes of carbon are even less abundant.
    ::氢的一个同位素核中有1个质子和0个中子,因此它有1个质子和1个中子。 氢的另一个同位素核中有1个质子和1个中子,因此它有2个质子和2个中子。 氢的第三个同位素核中有一个质子和2个中子,因此它有3个质子(质量为2个的氢的同位素有时被称为,质量为3个的氢的同位素有时被称为,但都是氢。 )碳有6个同位素;碳-11、碳-12、碳-13、碳-14、碳-15和碳-16。一个特定元素的同位素并非都同样丰富。例如,所有自然产生的碳的同位素98.9%是碳-12,大约1.1%是碳-13。碳的其他同位素甚至更少。

    The periodic table is a complete listing of all the known elements.
    ::周期表是所有已知要素的完整清单。

    Each element has its own square in the periodic table. The square contains the chemical symbol for the element, the atomic number, and the atomic weight . The atomic weight of an element is a weighted average of its isotopes.
    ::每个元素在周期表中有自己的正方形。方形包含元素的化学符号、原子数和原子权重。元素的原子权重是其同位素的加权平均值。

    A periodic table displaying elements with their chemical symbols, atomic numbers, and atomic weights.

    Example
    ::示例示例示例示例

    The element boron consists of two isotopes, boron-10 and boron-11. The abundance of boron-10 is 20.0% and the abundance of boron-11 is 80.0%. What is the atomic weight of boron?
    ::元素由两种同位素组成,即-10和-11。-10的丰度是20.0%,-11的丰度是80.0%。的原子重量是多少?

    @$\begin{align*}\text{Atomic weight} = (0.20)(10.0 \text{ amu}) + (0.80)(11.0 \text{ amu}) = 2.0 + 8.8 = 10.8 \text{ amu}\end{align*}@$
    ::@ $\ begin{ align{ text{ Atomic 重量} = 0. 20 (1.0 0\ text{ amu}) + 0. 80 (11.0\ text{ amu}) = 2. 0 + 8. 8 = 10. 8 = 10. 8 \ text{ amu{ end{ align} = 0. 0. 20 (1.0\ text{ amu})

    Use the PLIX Interactive below to make an isotope of helium.  Be sure to take note of what particle you add or remove to the atom to make this isotope:
    ::使用下面的 PLIX 交互作用来制造的同位素。 请注意您在原子上添加或删除的粒子, 以制造此同位素 :

    Summary
    ::摘要

    • Since the identification of the neutron, the model of the atomic nucleus has changed very little. According to this model, a nucleus is considered to be an aggregate of protons and neutrons.
      ::自确定中子以来,原子核的模型变化很小。 根据这一模型,核心被认为是质子和中子的总量。
    • The number of protons in a nucleus is called the atomic number and is designated by the symbol @$\begin{align*}Z\end{align*}@$ .
      ::核中的质子数称为原子数,由符号@$\ begin{ align\ end{ align} $指定。
    • The total number of nucleons, neutrons and protons, is designated by the symbol  @$\begin{align*}A\end{align*}@$ and is called the mass number.
      ::核子、中子和质子的总数由符号@$\ begin{align}A\end{align}$指定,称为质量号。
    • The number of neutrons, @$\begin{align*}N\end{align*}@$ , is @$\begin{align*}N = A - Z\end{align*}@$ .
      ::中子数, @ $\ begin{ align}N\ end{ end{ align} $, 是 @ $\ begin{ align} n = A - { end{ leign} $ 。
    • Nuclei that have the same number of protons in the nucleus but a different number of neutrons are called isotopes.
      ::核核中质子数量相同的核心核,但不同的中子数量被称为同位素。
    • Each element has its own square in the periodic table.
      ::每个元素在周期表中都有自己的平方。
    • Each elemental square on the periodic table contains the chemical symbol for the element, the atomic number, and the atomic weight.
      ::周期表中的每个元素方包括元素的化学符号、原子数和原子权重。
    • The atomic weight of an element is a weighted average of its isotopes.
      ::一个元素的原子权重是其同位素的加权平均数。

    Review
    ::回顾

    1. What do different isotopes of a given element have in common? How are they different?
      ::某一元素的不同同位素有什么共同点?它们有什么不同?它们有什么不同?
    2. What is the element name of the atom represented by @$\begin{align*}^{232}_{92} X\end{align*}@$ ?
      ::@$\ begin{ align\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\在\\\\\\\\\\\\在\\\\\\\\\\\\\\\\在\\\\\\\\\\\\\\\\\\\在\\\\\\\\\\\\\\\在\\\\\\\\\\\\\\\在\\\\\\\\\\在\\\\\\\\\\\\在\\\\\\\\\\\在\\\\\\\\\\\在\\\\\\\\\\\\在\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"$$$?\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
    3. How many protons and how many neutrons does the nucleus in problem #2 have?
      ::问题2的核有多少质子和多少中子?
    4. Using the following data, calculate the atomic weight of magnesium.
      ::使用以下数据计算镁的原子重量。

    Magnesium-24 = 78.70%
    ::-24 = 78.70%

    Magnesium-25 = 10.13%
    ::-25 = 10.13%

    Magnesium-26 = 11.17%
    ::26=11.17%

    Explore More
    ::探索更多

    Use this resource to answer the questions that follow.
    ::使用此资源回答下面的问题 。

    1. What is the difference between different isotopes of an element?
      ::元素的不同同位素之间有什么区别?
    2. Does changing the number of protons in an atom change the element? What about changing the number of neutrons?
      ::改变原子中的质子数量是否改变元素? 改变中子数量如何?
    3. How do isotope naming conventions work?
      ::同位素命名公约如何运作?