What is an atom, element, molecule, and compound? What is an
2017年3月29日 · An atom is a particle of matter that characterizes a chemical element. It is the smallest part of ordinary matter. It is made from particles called protons, neutrons and electrons called the subatomic particles. An element is a substance that is made entirely of one type of atom. For example, the element sodium is made up of only sodium atoms.
What are the 6 models of the atom? - Socratic
Jun 6, 2018. There are five basic atomic models which have contributed the structure of the atom itself. Explanation: They are: ⇒ John Dalton's atomic model: Dalton´s Billiard Ball (Solid Sphere) Model. ⇒ J.J. Thomson's model: Plum Pudding model. ⇒ Ernest Rutherford's model: Nuclear model. ⇒ Niels Bohr's model: Planetary model.
Valence Electrons - Chemistry - Socratic
The valence electrons are the electrons in the outermost electron shell of an atom. That is why elements whose atoms have the same number of valence electrons are grouped together in the Periodic Table. Generally, elements in Groups 1, 2, and 13 to 17 tend to react to form a closed shell, corresponding to the electron configuration s2p6.
Mass Number - Chemistry - Socratic
Answer: Well, the mass number of an atom is simply the number of massive, nuclear particles, protons, and neutrons.... And so for 1H, the mass number is simply 1; for 2H, the mass number is simply 2; for 3H, the mass number is simply 3. The isotopes contain 0, 1, 2 NEUTRONS respectively. Most of the heavier atoms have a range of isotopes, and ...
What is the electron configuration for As? - Socratic
2016年6月16日 · The complete electron for a neutral arsenic atom is: "1s"^2"2s"^2"2p"^6"3s"^2"3p"^6"3d"^(10)"4s"^2"4p"^3 Its shorthand electron configuration is: ["Ar"]"3d"^(10)"4s"^2"4p"^3 As is the chemical symbol for the element arsenic. Its atomic number is 33, which is the number of protons in the nuclei of its atoms. In a neutral atom, the number …
Isotopes - Chemistry - Socratic
An isotope is a variation of an element where the atom contains the same number of protons and electrons, but differs in the number of neutrons it contains in the nucleus. For example this shows three isotopes of Hydrogen. video from: enter link description here. Plmz1221 · · Oct 14 2014.
What electron configuration represents an atom in the ... - Socratic
2016年1月14日 · The excited state electron configuration of an atom indicates the promotion of a valence electron to a higher energy state. An electron configuration representing an atom in the excited state will show a valence electron promoted to a higher energy level. Example The ground state electron configuration of sodium is "1s"^2"2s"^2"2p"^6"3s"^1. In its excited state, the …
Why do atoms emit or absorb light of specific wavelengths?
2016年2月21日 · The electrons in an atom can only occupy certain allowed energy levels. When an electron drops from a higher energy level to a lower one, the excess energy is emitted as a photon of light, with its wavelength dependent on the change in electron energy. The electrons in an atom can only occupy certain allowed energy levels. This was one of the early results of …
Isotope Notation - Chemistry - Socratic
Isotope notation, also known as nuclear notation, is important because it allows us to use a visual symbol to easily determine an isotope's mass number, atomic number, and to determine the number of neutrons and protons in the nucleus without having to use a lot of words. Additionally, N = A −Z. Example 1: What is the isotopic notation for ...
How do you find core and valence electrons? + Example - Socratic
2018年8月9日 · Refer to the explanation. For the main group (representative) elements, the valence electrons are the outermost (highest energy) "s" and "p" electrons, which make up the valence shell. The valence electrons participate in chemical reactions. The main group elements are the A groups, or groups 1,2,13-18. The core electrons are in the inner shells and do not …