[Ar] 4s2 3d7
No, the noble gas notation for sulfur is [Ne] 3s2 3p4. This notation represents the electron configuration of sulfur using the nearest noble gas, which in this case is neon.
Noble gas notation is a way of simplifying electron configurations by using the previous noble gas's electron configuration as a starting point. For calcium, the electron configuration is: 1s2 2s2 2p6 3s2 3p6 4s2. Using the noble gas argon (1s2 2s2 2p6 3s2 3p6) as the starting point, the noble gas notation for calcium is [Ar] 4s2.
In full starting with 1s and through each level. The noble gas form, where only the electrons above the highest noble gas configuration are shown, the noble gas is in square brackets. Example chlorine 1s2, 2s2, 2p6, 3s2, 3p5 [Ne]) 3s2 3p5
Co is cobalt and is not a noble gas. Cobalt is a transition metal. Its electron configuration is [Ar]3d74s2.
The correct noble gas configuration for Li is neon (1s^2 2s^1).
[He] 2s1
The noble gas configuration for Sr (strontium) is [Kr]5s2
There is no boble gas notation for hydrogen and helium. The noble gas notation starts for elements after helium. The noble gas notation is a notation formed as a result of the electron configuration notation being used in conjunction with noble gases. The noble gas preceding the element in question is written then the electron configuration is continued from that point forward.
The noble gas notation is a notation formed as a result of the electron configuration notation being used in conjunction with noble gases. The noble gas preceding the element in question is written then the electron configuration is continued from that point forward. The notation is shorter to write and makes it easier to identify elements. The noble gas notation starts for elements after helium. For example, the electronic configuration of carbon is 1s2 2s2 2p2, whereas its noble gas notation is [He] 2s2 2p2.
The noble gas notation is a notation formed as a result of the electron configuration notation being used in conjunction with noble gases. The noble gas preceding the element in question is written then the electron configuration is continued from that point forward. The notation is shorter to write and makes it easier to identify elements. The noble gas notation starts for elements after helium. For example, the electronic configuration of carbon is 1s2 2s2 2p2, whereas its noble gas notation is [He] 2s2 2p2.
The noble gas configuration for Sr (strontium) is [Kr]5s2
The noble gas notation for the electron configuration of iron (Fe) is [Ar] 3d6 4s2, where [Ar] represents the electron configuration of the noble gas argon.
I am assuming that the question is for Co2+ ion. and the answer is [Ar] 3d5 4s2
[He] 2s1
The noble gas notation starts for elements after helium. Helium has no noble gas notation. Its electronic configuration is 1s2
[Ne] 3s2 3p6
The noble gas notation for Xenon is [Kr] 4d^10 5s^2 5p^6. This notation represents the electron configuration of Xenon with the closest noble gas element, Krypton, in brackets followed by the configuration for Xenon.