What is positive and what is negative in disinfection in medicine and the food industry if they use sterilization to kill bacteria?

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

Elements that do not have full outer electron shells will donate, share, or take electrons from other atoms. choose the items that have the correct binary ionic formula.

Using the periodic table, complete the table to describe each atom. type in your answers