How are elements in the modern periodic table arranged?
The elements in the modern periodic table are arranged based on their atomic numbers and chemical properties.
The periodic table is organized into rows called periods and columns called groups. Each element is represented by a unique symbol and placed in a specific location in the table.
The elements in each period are arranged sequentially in increasing atomic numbers from left to right. The first period contains only two elements (hydrogen and helium), while subsequent periods can have up to 32 elements.
The elements within each group possess similar chemical properties due to their similar electron configurations. There are 18 groups in the periodic table, labeled from 1 to 18. The elements in the same group often have the same number of valence electrons, which determines their chemical reactivity.
The periodic table also provides additional information about the elements, such as their atomic masses, atomic symbols, and electron configurations. It is a powerful tool used to study and understand the behavior and properties of different elements.
a
by decreasing atomic number
b
by increasing atomic number
c
by decreasing atomic mass
d
by increasing atomic mass
The elements in the modern periodic table are arranged by increasing atomic number, not decreasing atomic number. Therefore, option a is incorrect.
Option b is correct. The elements are arranged in increasing atomic number from left to right within each period in the periodic table.
Option c is incorrect. Although atomic mass does play a role in the organization of the periodic table, it is not the primary factor. The elements are primarily arranged by increasing atomic number.
Option d is also incorrect. The periodic table is not arranged by increasing atomic mass. Again, the primary factor determining the arrangement of elements is their increasing atomic number.