Q.What would be the IUPAC name and symbol for the element with atomic number 120?
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Element Nomenclature: What Do We Call an Element?
Imagine you discover a new island. You can't just call it "that place" — you need a name, a symbol on a map, and a way to write it in official documents. The same happens when scientists discover a new element. Element nomenclature is the system of naming, symbolising, and writing the names of chemical elements.
The Intuition: Why Bother with Rules?
Before the modern system, elements had chaotic names. Hydrogen was called "inflammable air," oxygen was "dephlogisticated air." Imagine memorising 118 such names. Worse, different countries used different names for the same element — iron was ferrum in Latin, loh in Hindi, Eisen in German. Scientists couldn't communicate clearly.
So the International Union of Pure and Applied Chemistry (IUPAC) stepped in. They created a universal system so that a chemist in Tokyo, a student in Mumbai, and a researcher in Paris all mean the same thing when they write "Fe" or "sodium."
The Precise Statement
Element nomenclature has three layers:
- The name — a unique, official English name (e.g., sodium, gold, carbon)
- The symbol — a one- or two-letter abbreviation (e.g., Na, Au, C)
- The systematic name — a temporary, descriptive name for newly discovered elements before they get a permanent name
Permanent name: chosen by discoverers, approved by IUPAC
Symbol: first letter capital, second letter lowercase (never "NA" or "na")
Systematic name: based on atomic number (e.g., element 118 = ununoctium, symbol Uuo)
The Rules in Detail
1. Permanent Names and Symbols
- First letter always capital, second letter always lowercase: Co (cobalt), not CO; Na (sodium), not NA.
- Symbols often come from Latin names: Ferrum → Fe (iron), Aurum → Au (gold), Stannum → Sn (tin).
- Some symbols come from German: Wolfram → W (tungsten).
- Newer elements are named after people, places, or properties: Curium (Cm) after Marie Curie, Californium (Cf) after California, Technetium (Tc) from Greek technetos (artificial).
Never write "CO" for cobalt — that's carbon monoxide. Never write "NA" for sodium — that's not a valid symbol. The case matters.
2. Systematic Names for New Elements
When a new element is discovered (say, element 117), it gets a temporary name until IUPAC approves a permanent one. The systematic name is built from the atomic number using these roots:
| Digit | Root |
|---|---|
| 0 | nil |
| 1 | un |
| 2 | bi |
| 3 | tri |
| 4 | quad |
| 5 | pent |
| 6 | hex |
| 7 | sept |
| 8 | oct |
| 9 | enn |
The name is formed by stringing the roots together, then adding -ium. For element 117: 1-1-7 = un-un-sept-ium = ununseptium (symbol Uus). When it got its permanent name, it became tennessine (Ts).
| Atomic number | Systematic name | Symbol | Permanent name |
|:---:|:---:|:---:|:---:|
| 113 | ununtrium | Uut | nihonium (Nh) |
| 115 | ununpentium | Uup | moscovium (Mc) |
| 117 | ununseptium | Uus | tennessine (Ts) |
| 118 | ununoctium | Uuo | oganesson (Og) |
3. Spelling and Pronunciation
- Names are not capitalised in English (except at the start of a sentence): "sodium chloride," not "Sodium chloride."
- British vs. American spelling: aluminium (UK) vs. aluminum (US) — both accepted, but IUPAC uses aluminium. …
The key idea is Element Nomenclature: IUPAC uses a systematic root + suffix system for elements beyond 100, based on the digits of the atomic number.
Reasoning:
- Atomic number 120 splits into digits: 1, 2, 0.
- IUPAC numerical roots: 1 =
un, 2 =bi, 0 =nil. - Combine roots in order:
un+bi+nil= unbinilium. …
Using the IUPAC digit roots, atomic number 120 (1-2-0) gives the name unbinilium and the symbol Ubn.
For an element not yet permanently named, IUPAC assigns a systematic name built from the digits of its atomic number, using one root per digit, then appending the suffix -ium.
Digit roots: 0=nil, 1=un, 2=bi, 3=tri, 4=quad, 5=pent, 6=hex, 7=sept, 8=oct, 9=enn.
Build the name for Z=120 — digits 1, 2, 0:
un+bi+nil+-ium=unbinilium …
- AP EAPCET 2024Set eng-2024-05-23-FN1 markMCQQ.Match the following List-I (Symbol of element) -- List-II (Group number) A. Mc -- I. 16 B. Lv -- II. 17 C. Fl -- III. 15 D. Ts -- IV. 14 The correct answer is (A) A-III, B-IV, C-I, D-II (B) A-IV, B-III, C-I, D-II (C) A-III, B-I, C-IV, D-II (D) A-II, B-IV, C-I, D-III
›Reveal solutionSolution
This tests knowledge of the newest (2016-named) superheavy p-block elements and their group placement; matching each symbol to its group gives A-III, B-I, C-IV, D-II.
Concept and Intuition
In 2016, IUPAC formally named four new synthetic elements completing period 7 of the periodic table — all superheavy elements made by fusing lighter nuclei in accelerators. They sit directly below their lighter p-block homologues, so their group number follows straight from their column position:
- Nihonium (Nh, 113) — group 13
- Flerovium (Fl, 114) — group 14 (below Pb)
- Moscovium (Mc, 115) — group 15 (below Bi)
- Livermorium (Lv, 116) — group 16 (below Po)
- Tennessine (Ts, 117) — group 17 (below At, a halogen)
- Oganesson (Og, 118) — group 18 (noble gas)
Step-by-Step Solution
- Identify each symbol: Mc = Moscovium (Z=115), Lv = Livermorium (Z=116), Fl = Flerovium (Z=114), Ts = Tennessine (Z=117).
- Place each in its group by column position in period 7: Mc → group 15, Lv → group 16, Fl → group 14, Ts → group 17.
- Match to the List-II labels: I = 16, II = 17, III = 15, IV = 14.
- So: A. Mc → 15 → III; B. Lv → 16 → I; C. Fl → 14 → IV; D. Ts → 17 → II. …
- AP EAPCET 2023Set eng-2023-05-16-AN1 markMCQQ.The IUPAC symbol for the element with atomic number 108 is (A) Hs (B) Bh (C) Mt (D) Sg
›Reveal solutionSolution
Atomic number 108 corresponds to Hassium, symbol Hs.
Concept and Intuition
Superheavy/transactinide elements are named systematically (and later officially) once discovered; their atomic numbers and symbols must simply be recalled/looked up. Elements 106–109 are Seaborgium (Sg, 106), Bohrium (Bh, 107), Hassium (Hs, 108), Meitnerium (Mt, 109).
Step-by-Step Solution
- List consecutive transactinide elements: Sg=106, Bh=107, Hs=108, Mt=109. …
- AP EAPCET 2021Set ap-2021-09-07-FN1 markMCQQ.If an element with atomic number Z=115 has been discovered today, in which of the following family would it had been placed and identify its electronic configuration. (A) Boron Family: [Ar]4f145d106s26p3 (B) Carbon Family: [Kr]5f146d107s27p3 (C) Nitrogen Family: [Rn]5f146d107s27p3 (D) Oxygen Family: [Xe]4f145d106s26p3
›Reveal solutionSolution
This tests predicting the group/family and electronic configuration of a superheavy element from its atomic number; the answer is (C).
Concept and Intuition
For a hypothetical/newly-discovered element, its family (group) is determined purely by its ground-state electronic configuration following the Aufbau order, since chemical family membership depends on the outermost (valence) subshell occupation — specifically the p-block group number equals (number of electrons in ns + np).
Step-by-Step Solution
- Z=115 is beyond Radon (Z=86), so the core is [Rn] (86 electrons).
- Remaining 115−86=29 electrons fill in order: 5f14 (14), 6d10 (10), 7s2 (2), 7p3 (3) — total 14+10+2+3=29. ✓.
- Configuration: [Rn]5f146d107s27p3. …
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