Electrons in an atom can be classified as core electrons and valence electrons. Valence electrons are those electrons which are present in valence shell and participates in bond formation. While, Core electrons are all remaining electrons which are not present in valence shell, hence not take part in bonding.
Atomic number of Selenium (Se) is 34 hence it has 34 electrons with following electronic configuration;
1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁴
From electronic configuration it is found that the valence shell is 4, and the number of electrons present in valence shell are 6. So,
Core Electrons = Total Electrons - Valence Electrons
Core Electrons = 34 - 6
Core Electrons = 28
Result:
There are 28 core electrons in Selenium.
Cu(NO3)2>NO2+CuO+O2 balanced: 2Cu(NO3)2=4NO2+2CuO+O2
Answer:
the answer of the questionis D Photons
Answer:
I would think C because you dont want to sell it (A), you dont want to conduct it or launch it agai, (B or D), so you would redesign it to make it better.
Ozone depleting chemicals are most likely belong to <u>halogen </u>group on the periodic table.
<h3>Ozone depleting chemicals are most likely to belong to which group on the periodic table?</h3>
Ozone depleting chemicals are the halogen group on the periodic table. Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), halons, methyl bromide, carbon tetrachloride, hydrobromo-fluorocarbons and methyl chloroform. Fluorine, chlorine, bromine, iodine, astatine and tennessine are the elements of halogen group elements. These elements greatly affected the ozone layer.
So we can conclude that Ozone depleting chemicals are most likely belong to halogen group on the periodic table.
Learn more about ozone here: brainly.com/question/5019112
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