Study Guides/Chemistry/First 20 Elements
Study Guide · Chemistry

List of the First 20 Elements of the Periodic Table

To understand basic chemistry, balance chemical equations, and draw electron configurations, a student must absolutely memorize the First 20 Elements of the modern Periodic Table in their exact order.

The elements are ordered precisely by their Atomic Number (the exact number of protons located inside the nucleus of their atoms).

Question (Click to Flip)

What is the 20th element of the periodic table?

Answer

The 20th element is Calcium (Ca), which has exactly 20 protons.

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Key Facts

Ordering Rule: Arranged strictly by increasing Atomic Number (number of protons).

Lightest Element: Hydrogen (Atomic Number 1).

Heaviest in the List: Calcium (Atomic Number 20).

Noble Gases Included: Helium (2), Neon (10), and Argon (18).

Odd Symbols: Sodium is 'Na' (Natrium) and Potassium is 'K' (Kalium).

Elements 1 to 10

  1. Hydrogen (H) - The lightest element in the universe.
  2. Helium (He) - A noble gas used in balloons.
  3. Lithium (Li) - A highly reactive metal used in batteries.
  4. Beryllium (Be)
  5. Boron (B)
  6. Carbon (C) - The basis of all living organisms on Earth.
  7. Nitrogen (N) - Makes up 78% of the Earth's atmosphere.
  8. Oxygen (O) - Essential for human breathing and fire.
  9. Fluorine (F)
  10. Neon (Ne) - A glowing noble gas used in bright signs.

Elements 11 to 20

  1. Sodium (Na) - (The symbol 'Na' comes from its Latin name Natrium).
  2. Magnesium (Mg)
  3. Aluminum (Al) - A light, strong metal used in airplanes and foil.
  4. Silicon (Si) - A metalloid crucial for computer chips.
  5. Phosphorus (P)
  6. Sulfur (S) - A bright yellow, foul-smelling non-metal.
  7. Chlorine (Cl) - A toxic green gas used to purify swimming pools.
  8. Argon (Ar) - A noble gas used inside lightbulbs.
  9. Potassium (K) - (The symbol 'K' comes from its Latin name Kalium).
  10. Calcium (Ca) - Crucial for building strong human bones and teeth.

Mnemonic Trick to Memorize

Memorizing 20 names in order can be hard. Use this classic memory sentence (where the first letter of each word matches the element):

Hi Hello Little Beryllium Boy, Can Not Orphans Find New Nations, Magistrates Always Sing Pop Songs, Clear Argon Kills Cats.

Questions and Answers

What is the 20th element of the periodic table?+

The 20th element is Calcium (Ca), which has exactly 20 protons.

Why is the symbol for Sodium 'Na'?+

Because the symbols for early elements were derived from ancient languages. The Latin name for Sodium is 'Natrium'.

Which of the first 20 elements are noble gases?+

Helium, Neon, and Argon are the three highly stable, unreactive noble gases found in the first 20 elements.

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