The first 30 elements of the periodic table range from Hydrogen (H, Z=1) to Zinc (Zn, Z=30). These include non-metals, noble gases, alkali metals, alkaline earth metals, and the first row of transition metals (Z=21 to 30). Memorising their names, symbols, and atomic numbers is essential for chemistry.
Elements 1–30 span Period 1 (H, He) through the start of Period 4 (K to Zn).
Hydrogen (H, Z=1) is the lightest and most abundant element in the universe.
The transition metals begin at Scandium (Sc, Z=21) and end at Zinc (Zn, Z=30) in the first row.
Cr (Z=24) has configuration [Ar] 3d⁵ 4s¹ and Cu (Z=29) has [Ar] 3d¹⁰ 4s¹ — both Aufbau exceptions.
Iron (Fe, Z=26) is the most widely used metal and essential for haemoglobin.
Fluorine (F, Z=9) is the most electronegative element.
Silicon (Si, Z=14) is the second most abundant element in Earth's crust.
Argon (Ar, Z=18) is the most abundant noble gas in Earth's atmosphere (~0.93%).
| Atomic No. | Symbol | Name | Category | Key Property |
|---|---|---|---|---|
| 1 | H | Hydrogen | Non-metal | Lightest element; makes up stars |
| 2 | He | Helium | Noble gas | Used in balloons; inert |
| 3 | Li | Lithium | Alkali metal | Lightest metal; used in batteries |
| 4 | Be | Beryllium | Alkaline earth | Hard, lightweight metal |
| 5 | B | Boron | Metalloid | Semiconductor behaviour |
| 6 | C | Carbon | Non-metal | Basis of organic chemistry |
| 7 | N | Nitrogen | Non-metal | 78% of atmosphere |
| 8 | O | Oxygen | Non-metal | 21% of atmosphere; essential for life |
| 9 | F | Fluorine | Halogen | Most electronegative element |
| 10 | Ne | Neon | Noble gas | Used in neon signs |
| Atomic No. | Symbol | Name | Category | Key Property |
|---|---|---|---|---|
| 11 | Na | Sodium | Alkali metal | Na from Latin 'Natrium'; NaCl = table salt |
| 12 | Mg | Magnesium | Alkaline earth | Burns with bright white flame |
| 13 | Al | Aluminium | Post-transition metal | Most abundant metal in Earth's crust |
| 14 | Si | Silicon | Metalloid | Basis of semiconductors and glass |
| 15 | P | Phosphorus | Non-metal | Essential for DNA, ATP; matches |
| 16 | S | Sulphur | Non-metal | Used in H₂SO₄ manufacture; volcanic |
| 17 | Cl | Chlorine | Halogen | Used in water purification; bleach |
| 18 | Ar | Argon | Noble gas | Most abundant noble gas in atmosphere |
| 19 | K | Potassium | Alkali metal | K from Latin 'Kalium'; essential for nerves |
| 20 | Ca | Calcium | Alkaline earth | Found in bones, teeth; limestone |
| Atomic No. | Symbol | Name | Key Property | Electronic Config |
|---|---|---|---|---|
| 21 | Sc | Scandium | First transition metal; used in aerospace | [Ar] 3d¹ 4s² |
| 22 | Ti | Titanium | Lightweight, strong; used in aircraft | [Ar] 3d² 4s² |
| 23 | V | Vanadium | Catalyst in contact process (V₂O₅) | [Ar] 3d³ 4s² |
| 24 | Cr | Chromium | Stainless steel; [Ar] 3d⁵ 4s¹ (exception) | [Ar] 3d⁵ 4s¹ |
| 25 | Mn | Manganese | Steel making; MnO₂ in batteries | [Ar] 3d⁵ 4s² |
| 26 | Fe | Iron | Most used metal; haemoglobin (Fe²⁺) | [Ar] 3d⁶ 4s² |
| 27 | Co | Cobalt | Vitamin B₁₂; alloys; blue pigment | [Ar] 3d⁷ 4s² |
| 28 | Ni | Nickel | Coinage; stainless steel; catalyst | [Ar] 3d⁸ 4s² |
| 29 | Cu | Copper | Electrical wiring; [Ar] 3d¹⁰ 4s¹ (exception) | [Ar] 3d¹⁰ 4s¹ |
| 30 | Zn | Zinc | Galvanising; batteries; enzyme cofactor | [Ar] 3d¹⁰ 4s² |
Period 1 (2 elements): H (1), He (2) Period 2 (8 elements): Li (3), Be (4), B (5), C (6), N (7), O (8), F (9), Ne (10) Period 3 (8 elements): Na (11), Mg (12), Al (13), Si (14), P (15), S (16), Cl (17), Ar (18) Period 4 (first 12 elements): K (19), Ca (20), Sc (21), Ti (22), V (23), Cr (24), Mn (25), Fe (26), Co (27), Ni (28), Cu (29), Zn (30)
Group classification:
Popular mnemonics for first 20 elements: 'Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon' → 'Hi Hello Little Betty Brown Can Not Obtain Fresh Neon'
Elements 11–20: 'Sodium Magnesium Aluminium Silicon Phosphorus Sulphur Chlorine Argon Potassium Calcium' → 'Naughty Magpies Always Sit Perched Silently Clucking Around Peaceful Countryside'
Transition metals 21–30 (Sc Ti V Cr Mn Fe Co Ni Cu Zn): → 'Scared Tigers Venture Crookedly, Meandering Far Coastward Nibbling Cookies Zealously'
Aufbau exceptions to remember:
H, He, Li, Be, B, C, N, O, F, Ne, Na, Mg, Al, Si, P, S, Cl, Ar, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn (Hydrogen to Zinc).
Chromium (Cr, Z=24) with configuration [Ar] 3d⁵ 4s¹ (expected 3d⁴ 4s²) and Copper (Cu, Z=29) with [Ar] 3d¹⁰ 4s¹ (expected 3d⁹ 4s²) are the Aufbau exceptions among elements 1–30.
Elements 21–30 are first-row transition metals: Scandium (Sc), Titanium (Ti), Vanadium (V), Chromium (Cr), Manganese (Mn), Iron (Fe), Cobalt (Co), Nickel (Ni), Copper (Cu), and Zinc (Zn).
The noble gases in elements 1–30 are: Helium (He, Z=2), Neon (Ne, Z=10), and Argon (Ar, Z=18), all in Group 18.
The halogens in elements 1–30 are: Fluorine (F, Z=9) and Chlorine (Cl, Z=17), both in Group 17. Fluorine is the most electronegative element.
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