Ionic bond is a compound made up of a meta and a non-metal eg NaCl (sodium chloride)
covalent bond is made up of two non-metals eg H2O (water)
B is correct. Krypton is a noble gas which has a full outer shell of 8 electrons and is generally unreactive because of it.
The answer is B
Hope this helps
When the human body (its cells) is exposed to radiation (X rays and gamma rays), electrons are emitted from atoms and molecules. ... ・These radicals react immediately with surrounding atoms, causing abnormal chemical reactions (or, minor damage to localized areas of cells).
