Alkali metals - s block; one valence electron; lose one valence electron; charge of an ion +1
Step-by-step explanation:
Alkali metals have electronegativity from 0.7 to 1, lowest in Periodic table of elements, which means that alkali metals (I group in Periodic table) has positive oxidation number in compounds.
Electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.
For example, sodium (Na) is an element with atomic number 11 and it has one valence electron (3s¹) like all alkaline metals.
Electron configuration of sodium atom: ₁₁Na 1s² 2s² 2p⁶ 3s¹.
2) Alkaline earth metals - s block; two valence electrons; lose two electrons; charge of an ion is +2.
Beryllium, magnesium,calcium and strontium are alkaline earth metals. The elements have very similar properties. Alkaline earth metals have in common an outer s- electron shell (two electrons).
For example, atomic number of calcium is 20, it means that it has 20 protons and 20 electrons, so atom of calcium is neutral.
Electron configuration of calcium atom: ₂₀Ca 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²; calcium has two valence electrons (4s²).
3) Boron group - p block; three valence electrons; lose three electrons; charge of metal ions is +3; no nonmetals in this group; none.
For example, boron is an element with atomic number 5, which means it has 5 protons and 5 electrons, bcause atom has neutral charge.
Electron configuration of boron: ₅B: 1s² 2s² 2p¹, it has three valence electrons in 2s and 2p orbitals.
Atomic number is the number of protons, which is characteristic of a chemical element.
4) Carbon group - p block; four valence electrons; lose two or four electrons; charge of metal ions is +2 or +4; nonmetals gain four electrons; charge of nonmetals is -4.
Carbon (C), silicon (Si), germanium (Ge), tin (Sn), lead (Pb) and flerovium (Fl) are in group 14 of Periodic table. They have same number of valence electrons (four) and similar chemical properties.
For example, carbon is a chemical element with symbol C and atomic number 6, which means it has 6 protons and six electrons. Valence electrons are in 2s and 2p orbitals.
Electron configuration of carbon atom: ₆C 1s² 2s² 2p².
5) Nitrogen group - p block; five valence electrons; lose three or five electrons; charge of metal ions is +3 or +5; nonmetals gain three electrons; charge of nonmetals is -3.
Nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi) and moscovium (Mc) are in group 15 of Periodic table. They have same number of valence electrons (five).
For example, bizmuth (Bi) has atomic number 83, it has 83 protons and 83 electrons. Valence electrons are in 6s and 6p orbitals.
Electron configuration of bizmuth atom: ₈₃Bi [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p³.
6) Oxygen group - p block; six valence electrons; lose four or six electrons; charge of metal ions is +4 or +6; nonmetals gain two electrons; charge of nonmetals is -2.
Oxygen (O), sulfur (S), selenium (Se), tellurium (Te) and the radioactive element polonium (Po) are in group 16 of Periodic table. They have same number of valence electrons (six).
For example, electron configuration of oxygen atom: ₈O 1s² 2s² 2p⁴.
Oxygen atom has six valence electrons (2s² 2p⁴), so it is in 16 group of Periodic table of elements.
7) Halogens - p block; seven valence electrons; nonmetals gain one electron; charge of nonmetals is -1.
Halogen elements are in group 17: fluorine (F), chlorine (Cl), bromine (Br) and iodine (I). They are very reactive and easily form many compounds.
Halogens need to gain one electron to have electron cofiguration like next to it noble gas.
For example, fluorine has 9 electrons and it gain easily one electron in chemical reaction to have electron configuration like noble gas neon (Ne) with 10 electrons.
Electron configuration of fluorine: ₉F 1s² 2s² 2p⁵.
8) Noble gases - p block; eight valence electrons (except helium with two valence electrons); do not gain or lose electrons; none.
Noble gases (group 18) are in group 18: helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn). They have very low chemical reactivity.
Noble gases have very stable electron configuration and does not need to gain electrons, only when they gain energy .
Helium has atomic number 2, it has 2 protons and 2 electrons.
Electron configuration of helium atom: ₂He 1s².
Electron configuration of krypton atom:
₃₆Kr 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶.
