The first element in a period is an alkali metal.
Helium is in the first period of the periodic table.
The first element in the fourth period of the periodic table is potassium with the atomic number 19.
Sodium (Na) has the lowest first ionization energy in period 3.
Period 1 refers to the top row of the periodic table. These elements are Hydrogen and Helium.
The first element in the fourth period, which is used in making fertilizer, is potassium.
The first element in the fourth period of the periodic table is potassium (K).
The first element in period three of the periodic table of chemical elements is sodium (Na).
The first element in the fourth period of the Periodic Table is potassium (K).
Hydrogen
hydrogen
Helium is in the first period of the periodic table.
The first element in the fourth period of the periodic table is potassium with the atomic number 19.
Potassium
The second element in Period 3 is Magnesium, with an atomic number of 12.
It is potassium.
Potassium (K)
potassium