Question

From the symbol ${\text{X}}_2^4$, identify the element and write down its mass number and atomic number.

Answer 1

Understanding the concept:

• An element is a substance that is made up of only the same type of atoms.
• For example, Sodium elements are made up of only sodium atoms.

Explanation of symbol of an element:

• An element name is abbreviated with a one- or two-letter symbol. The initial letter of a two-letter symbol is usually capitalized, whereas the second letter is always lowercase.
• The symbol C, for example, stands for carbon, while the letters Na, K, and Cl stand for sodium, potassium, and chlorine, respectively.
• The initial letter of a sign has always been written in uppercase, whereas the 2nd letter has always been written in lowercase.
• Other symbols were drawn from element names in Latin, German, and Greek.
• Iron, for example, has the symbol Fe, which derives from the Latin name Ferrum
• The symbol ${\mathrm{X}}_2^4$ represents the element Helium(He) in a modern periodic table.
• Its atomic number is equal to 2, represents as a subscript ${\mathrm{He}}_2$, equal to a number of protons (or electrons).
• The mass number is equal to 4, represents as a superscript ${\mathrm{He}}^4$, equal to the sum of protons and neutrons.