Which of the following statements is/are correct regarding the Modern Periodic Table?

I. Properties of elements are a periodic function of their atomic mass.

II. The Modern Periodic Table has 18 vertical columns known as ‘groups’ and 7 horizontal rows known as ‘periods’.

The correct answer is Option 3.

Key Points

• The Modern Periodic Table consists of 18 vertical columns known as 'groups' and 7 horizontal rows known as 'periods'.
• The Modern Periodic Table is structured based on the atomic number of elements, not their atomic mass.
• Each group in the periodic table has elements with similar chemical properties due to the same number of valence electrons.
• Periods in the periodic table represent the number of electron shells an element's atoms have.
• The arrangement of elements in the Modern Periodic Table helps predict the properties of elements and their compounds.

Additional Information

• Mendeleev's Periodic Table
  • Dmitri Mendeleev created the first periodic table, arranging elements by increasing atomic mass and grouping them by similar properties.
  • Mendeleev left gaps for undiscovered elements and predicted their properties accurately.
  • The limitations of Mendeleev's table were addressed with the discovery of the atomic number.
• Atomic Number
  • The atomic number is the number of protons in an atom's nucleus and determines the element's identity.
  • The modern periodic law states that the properties of elements are a periodic function of their atomic numbers.
• Periodic Trends
  • Periodic trends include atomic radius, ionization energy, electronegativity, and electron affinity.
  • These trends help predict the behavior of elements in chemical reactions.
• Lanthanides and Actinides
  • The Lanthanides and Actinides are two series of elements often displayed below the main table.
  • They include elements with atomic numbers 57-71 (Lanthanides) and 89-103 (Actinides).