Chemistry · Periodic Classification Of Properties · NEET
Write its full electronic configuration, then look ONLY at the outermost shell (the shell with the highest n value). For Z=114 the configuration ends in 7s2 7p2. The outer shell has 2 + 2 = 4 electrons in s and p. For p-block elements, Group = 10 + (s + p outer electrons) = 10 + 4 = 14. So Z=114 is in Group 14, the carbon family. You never need to look at inner filled shells like 5f14 or 6d10.
Because f and d subshells are inner shells for these elements, not the valence (outermost) shell. The group of a main-group (s or p block) element is decided only by the electrons in its highest-n shell. For Z=114 the highest n is 7, so only 7s2 and 7p2 count. The 5f14 and 6d10 are completely filled inner shells and act like the noble-gas core.
1) Start from the nearest noble gas below it. 2) Keep filling orbitals in the normal Aufbau order. For Z=114, start from Rn (Z=86), then add 28 more electrons: 5f14 (14), 6d10 (10), 7s2 (2), 7p2 (2) = 28. So Z=114 = [Rn] 5f14 6d10 7s2 7p2. Count the outer 7s and 7p electrons to get the group.
Z=119: one electron past Z=118 (which finishes period 7). The 119th electron starts the 8th shell as 8s1, giving [Uuo] 8s1. Valence shell ns1 means Group 1, the alkali metals. Z=120: [Uuo] 8s2, valence ns2, which is Group 2, the alkaline earth metals. Here [Uuo] means the core of element 118 (oganesson).
Carbon family. This is a common NEET trap. The outer shell is 7s2 7p2, which matches ns2 np2 like carbon (2s2 2p2), silicon and germanium. Nitrogen family (Group 15) would need ns2 np3. Since Z=114 has only p2, not p3, it is Group 14, carbon family.
IUPAC gives a temporary systematic name from the digits of the atomic number (un=1, enn=9, etc.), but the name does NOT tell you the group. To get the group you still write the configuration and read the valence shell. So for Z=119 the name is ununennium, but the group (Group 1) comes from its 8s1 valence electron, not from the name.
The element Z = 114 has been discovered recently. It will belong to which of the following family/group and electronic configuration?
The IUPAC name of an element with atomic number 119 is:
Try the real previous-year questions from this chapter — each with the answer and a full solution.
For s-block: Group = number of outer s electrons (ns1 = Group 1, ns2 = Group 2). For p-block: Group = 10 + (outer s + p electrons). Example: 7s2 7p2 gives 10 + 4 = 14.
The period equals the highest principal quantum number n in the configuration. Z=114 has highest n = 7, so it is in period 7. Z=119 and 120 start n = 8, so they belong to period 8.
NCERT notes that recently discovered elements above Z=112 are synthesised in labs (man-made), not found in nature. As of the NCERT text, elements up to Z=118 have been discovered, and Z=119 and 120 were still undiscovered.
[Uuo] is just shorthand for the electron core of element 118 (oganesson), the last noble gas of period 7. Writing [Uuo] 8s1 or [Uuo] 8s2 is the same idea as writing [Rn] or [Xe] for a core, it saves you from writing all 118 electrons.
NEET repeatedly asks you to place a new element (Z=114, 117, 118, 119) into a group and write its configuration. If you master the valence-shell method, you solve these in seconds without memorising a giant periodic table.
