Answer:
C) Cl2
Step-by-step explanation:
Covalent bonds are when atoms are non-metal. No metals are involved.
By referencing the periodic table, we can determine their columns or groups, which shows their families and whether each of these elements are metal or non-metal.
A) Be is berylium, in the second column (group 2A), which are Alkaline Earth Metals. Since Be is a metal, BeCl2 cannot be covalent.
B) Ca is Calcium, in the second column (group 2A), which are Alkaline Earth Metals Since Ca is a metal, CaCl2 cannot be covalent.
C) The only atom is Cl, which is chlorine. It is in the 17th group or group 7A. These are halogens, a type of non-metal. This can be covalent because there are only non-metal.
D) Ti is titanium. It's in the middle section, the transition metals. Because its a metal, TiN cannot be covalent.