I believe it is a crystal, read it in a chemistry book over last summer so might be off
Option 2, Br. I'll go over why all other three options are incorrect.
Option 1 - Krypton is a Noble gas, and so it doesn't need to accept electrons since it has an octet.
Option 3 and 4 - Both Calcium and Barium are alkaline earth metals, and give away electrons, since they only have 2.
-T.B.
Answer:
B2O3
Explanation:
good luck have a nice day
Circulate and move within a liquid or gas.
