Final answer:
Group 2 metals primarily react with elements in Groups 16 and 17 to form ionic compounds. A binary ionic compound between Beryllium and Chlorine results in the formula BeCl2.
Step-by-step explanation:
The elements in Group 2 (the alkaline earth metals) most likely react with the halogens (Group 17) and the oxygen group (Group 16), as these groups tend to form ionic bonds by accepting the two electrons that Group 2 metals are likely to lose.
When Beryllium (Be) and Chlorine (Cl) combine to form a binary ionic compound, the formula would be BeCl2, highlighting the 1-to-2 ratio that balances the charges of Beryllium (+2) and Chlorine (-1) respectively.