Chemistry问题1:An element is a substance that is made up of only one kind of atoms.One kind是指同一个的atom,还是Metal或者non-metal两大类中的一类?2:an element=an atom?有什麼分别?最好举个例子. 相关知识点: 试题来源: 解析 1.化学元素是根据原子核电荷的多少对原子进行分类的一种方法,把核...
Once the relative mass scale was made, later experiments were able to relate the mass in grams of a substance to the number of atoms and an atomic mass unit—amu was found; 1 amu or Dalton is equal to 1.66×10-24 grams. At this time, chemists knew the atomic masses of elements and...
Each kind of atom makes up a pure substance called an element. You may have heard of oxygen, lead, and gold. Well, these are all examples of elements. Can you believe that a pure gold necklace is made up of billions of gold atoms? View Video Only Save Timeline Video Quiz ...
AnElectric Dipoleis formed from a substance that possesses two equal electric charges of opposite sign separated by a small distance. The best example of an electric dipole is an atom with one electron and one proton (Hydrogen). The proton acts as the source of positive charge, while the el...
Create an account Ask a question Our experts can answer your tough homework and study questions. Ask a question Search AnswersLearn more about this topic: Pure Substance in Chemistry | Definition, Properties & Examples from Chapter 5 / Lesson 13 432K What is a pure substance in chemistry...
A substance that cannot be broken down into simpler substances by chemical means is called a/an:A) ElementB) CompoundC) MoleculeD) AtomAnswer: A 相关知识点: 试题来源: 解析 A 题目询问无法通过化学方法分解为更简单物质的名称。选项分析如下:A) 元素(Element):由单一类型原子组成,无法被化学手段进...
Nuclear fission is the splitting of the nucleus of an atom. Only a few elements are suitable for use in this way, the most important ones being Uranium-235, Uranium-233, and Plutonium-239. When a nucleus of one of these elements is struck by a free neutron it breaks down into two lig...
Ask a question Search AnswersLearn more about this topic: Atom | Definition, Composition & Examples from Chapter 2 / Lesson 1 268K Learn the definition of an atom, what atoms contain, the nucleus in the middle of an atom, what atoms look like, and examples of atoms. Related...
An atom is a piece of matter that exists in all substances that can physically be touched. An atom contains three kinds of particles: protons, neutrons and electrons. The protons and neutrons create the nucleus while the electrons fly around and above th
Ask a question Search AnswersLearn more about this topic: Atom Definition, Structure & Examples from Chapter 14 / Lesson 1 38K Learn about the parts of an atom and its overview and structure. Discover the neutrons, protons, and electrons that compose an atom, along with examples of atom...