Na-short for Natrium (Latin Name for Sodium)
The chemical element "sodium" is an alkali metal.
Sodiums chemical symbol is 'Na'. 'Na' is the initials of the Latin word for sodium, which is ' NADIUM'. Similarly, Potassium (K) is from Latin for 'KALIUM'.
The elemental symbol for Platinum is Pt.
The chemical abbreviation for Ferric Ammonium Oxalate is FeNH4C2O4.
The chemical symbol for methane is CH4.
Helium doesn't have an abbrevaition but its chemical symbol is He.
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H is the abbreviation on the table of elements. The 'chemical symbol' for hydrogen is H.
m.p. According to CAS (Chemical Abstracts Service, a division of American Chemical Society) Standard Abbreviation & Acronym.
HCO3 is the medical and chemical abbreviation meaning bicarbonate.
Carbon.
It is an abbreviation for a chemical element.