To find the atomic number of an element in the periodic table based on its group number and period number, you can use the following steps:
Identify the element's period number: The period number corresponds to the row in which the element is located in the periodic table. The first period (row) contains elements with atomic numbers 1 and 2, the second period contains elements with atomic numbers 3 to 10, and so on.
Determine the element's group number: The group number represents the column in which the element is found within its respective period. The group number can provide information about the element's electron configuration and its chemical properties.
Calculate the atomic number: Once you have the element's period number and group number, you can calculate the atomic number by using the following formula: Atomic Number = (Group Number - 1) × Number of Periods + Period Number
For example, let's say you want to find the atomic number of an element located in period 4, group 13. Applying the formula, we get: Atomic Number = (13 - 1) × 4 + 4 Atomic Number = 12 × 4 + 4 Atomic Number = 48 + 4 Atomic Number = 52
Therefore, the element in period 4, group 13 has an atomic number of 52.
It's worth noting that the periodic table can have variations in the labeling of groups and periods, but the general principles remain the same.