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Atomic Mass of Sodium

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What is the Atomic Mass of Sodium? – Chemistry Q&A

(a). 22 g/mol

(b). 23 g/mol

(c). 11 g/mol

(d). 20 g/mol.

Answer: (b)

Explanation: The atomic mass of an element can be calculated using the element’s atomic number and the number of neutrons present. Sodium has an atomic number of 11.

The following formula was used: Number of neutrons + Number of protons

Sodium is a metal that belongs to the alkali family. It is the first element of the third periodic period in the periodic table. In the periodic table, it is the eleventh element. Therefore,

The atomic number of sodium is 11, while the number of neutrons in its nucleus is 12.

Sodium’s atomic mass is 11 + 12 = 23.

As a result, 1 mole of sodium equals 23 grams.

We know that because sodium’s atomic mass is 23, we can write it as 23 g/mol.

Important terms to know:

  • The number of protons in the nucleus of each atom of a chemical element is known as its atomic number.The only way to identify a chemical element is by its atomic number. It is the same as the charge number of the nucleus. The number of electrons in an uncharged atom is also equal to the atomic number. The sign Z stands for atomic number.
  • The mass of an atom is its atomic mass. Although the kilogramme is the SI unit of mass, the atomic mass is sometimes stated in the non-SI unit dalton, which is defined as 1/12 of the mass of a single carbon-12 atom at rest. Protons and neutrons in the nucleus make up nearly all of an atom’s mass, with electrons and nuclear binding energy playing a minor contribution. As a result, when stated in daltons, the numeric value of the atomic mass is roughly equal to the mass number.