4. Atoms and Elements

In the periodic table, the symbol $Cl$ corresponds to which element?

Which element has an atomic number of $80$ (i.e., $80$ protons in its nucleus)?

Periodic Table: Element Symbols — What is the chemical symbol for the element sodium?

Which element is a neutral atom with 38 electrons?

Which element has 6 protons in its nucleus?

Which element has $74$ protons (atomic number $74$)?

Which element has 17 protons in its nucleus?

A neutral atom has 17 electrons. Which element is it?

Which element is located in Group 2 and Period 3 of the periodic table?

Which element has 30 protons in its nucleus?

Which element has 50 protons (atomic number $50$)?

Which element has 13 protons (i.e., atomic number $13$)?

Why does the fourth period in the periodic table contain 18 elements?

Which element has $83$ protons in its nucleus?

The periodic table organizes elements in order of increasing which property?