The first 20 elements of the periodic table

Explanation

This is an acronym-style memory sentence. Each word's first letter (or first two letters) matches the chemical symbol of the element it stands for:

• Happy - H (Hydrogen)
• Henry - He (Helium)
• Lives - Li (Lithium)
• Beside - Be (Beryllium)
• Boron - B (Boron)
• Cottage - C (Carbon)
• Near - N (Nitrogen)
• Our - O (Oxygen)
• Friend - F (Fluorine)
• Nelly - Ne (Neon)
• Nancy - Na (Sodium)
• Mg - Mg (Magnesium)
• Allen - Al (Aluminum)
• Silly - Si (Silicon)
• Patrick - P (Phosphorus)
• Stays - S (Sulphur)
• Close - Cl (Chlorine)
• Arthur - Ar (Argon)
• Kisses - K (Potassium)
• Carrie - Ca (Calcium)

For mnemonics covering the rest of the periodic table by group, see Mnemonic Devices for the Periodic Table.

Alternative mnemonics

• Here He Lies Beneath Bed Clothes, Nothing On, Feeling Nervous, Naughty Margret Always Sighs, " Please Stop Clowning Around " (18 elements)
• How He Likes Bear By Cups Not Overflowing. Although Science Presents Some Clues, Are Kittens Cats?
• Hi, Hello! Little Beryll Brown Cracking Nuts On Friday. Nellie's Naughty Magpie Always Sings Pop Songs Clearly After Killing Cathy.

Find the average atomic mass

Rules to find the average atomic mass, if the atomic number (Z) is an: Even number except Be (9), Ar (40),

• multiply the atomic number by 2. For example,
  • 1. Helium atomic number (Z) is the EVEN #2, hence to find the average atomic mass (A) is (Atomic number) multiply by 2 which is 2 x 2 = 4

Odd number except H (1), N (14 ), Cl (35.5),

• multiply the atomic number by 2, then add 1. For example,
  • 1. Lithium atomic number (Z) is the ODD # 3, hence to find the average atomic mass (A ) is (Atomic number) multiply by 2 plus 1, which is 3 x 2 +1 = 7
  • 2. Boron atomic number (Z) is the ODD # 5, hence to find the average atomic mass (A ) is (Atomic number ) multiply by 2 plus 1, which is 5 x 2 +1 = 11

Please remember the exception to the rules:

• Be, Ar, H, N, Cl

Song for the first 20 elements

Many more mnemonics for remembering the elements of the periodic table See https://en.wikipedia.org/wiki/Periodic_table for more information.