The simply answer is that in the outer shell each of the halogens have only seven electrons, this is the reason why they are the most reactive nonmetals, they wish to require a further electron to become stable.
Fluorine (F) Atomic number 9 [He] 2s22p5 note the second shell is the outer shell and has only 7 electrons, to be stable it has to have eight.
Chlorine (Cl) Atomic number 17 [Ne] 3s23p5 note this its the third shell which is the outer shell and has only 7 electrons, to be stable it has to have eight.
For Bromine (Br) we find its the fourth shell is the outer shell which has seven elections, and finally Iodine (I) we find its the fifth shell which is the outer shell and it has only 7 electrons, to be stable it has to have eight.
Hope this helps
Halogen bulbs are sensitive to oils in the human hand so you should always wear latex gloves or use something to cover your hand or the bulb will no longer function once you turn it on. Halogen bulbs are commonly used in dance club lighting and when i DJ'd i'd have to keep some gloves handy.
Its called the electron shell. Electrons will always fill up low orbitals first in the shell, an then as more energy is added to the atom, the electrons move up an orbit, then release the energy in some form, and they move back down to the lowest energy orbit.
An element, as opposed to a compound or mixture.
The whole number, the one at the top, above the element's symbol in the element box, is the atomic number. The atomic number is the number of protons per atom in that particular element. The bottom number, that is always a decimal, is the atomic mass.
Yes, the number of protons is always used to identify an element. This is also known as its atomic number.
Astatine, the always radioactive one.
Astatine, the always radioactive one.
102 ( the atomic #, # of protons, and #of electrons are always the same )
That is not true. The first element in a period may be active or inactive, depending on the specific electron configuration of the element. For example, the first element in period 1, hydrogen, is not considered an active element.
Noble gases, such as helium, neon, and argon, always exist in monatomic form because they have a stable electron configuration with a full outermost energy level.
An iodine atom has the same number of electrons as a bromine ion. Both elements belong to the halogen group and have seven valence electrons. When bromine gains one electron to become an ion, it will have a full outer shell with eight electrons, the same electron configuration as iodine.
1s 2 2s 2 2p6 3s2 3p6 4s2 or Ar 4s2 (Noble gas form) In noble gas form, you go back to the noble gas (the last group on the Periodic Table) prior to the element you are writing the configuration for. The electron configuration is the same up until that point. Then you write down the difference. In this example, the electron configuration for Argon (Ar) is 1s2 2s2 2p6 3s2 3p6. If you fill up the shells until 4s2, you get calcium. It's faster to abbreviate by saying "Ar 4s2"
The oxidation number of the element potassium (K) is +1. This is because alkali metals like potassium typically lose one electron to achieve a stable electron configuration.
Barium loses electrons to obtain a stable octet, like any other metal.
Fluorine is the most electronegative element, so it tends to attract electrons strongly and form a single covalent bond with one electron from another element. This results in a stable electronic configuration, leading to an oxidation number of -1.
Electron arrangement determines the chemical properties and reactivity of an element or compound. It governs how atoms interact with each other to form bonds, which influences their physical and chemical properties. Understanding electron arrangement helps predict how an element will behave in different chemical reactions and environments.
No, the electron configuration for an ion is not always the same as that of its nearest noble gas. When an atom loses or gains electrons to form an ion, its electron configuration changes. For example, a sodium ion (Na⁺) has the electron configuration of [Ne], which is the same as neon, but a chloride ion (Cl⁻) also has the same configuration as argon ([Ar]). Thus, while some ions can have configurations similar to noble gases, this is not universally true for all ions.