Answer:
4
Explanation:
Carbon has four valence electrons, so it can achieve a full outer energy level by forming four covalent bonds. When it bonds only with hydrogen, it forms compounds called hydrocarbons. Carbon can form single, double, or triple covalent bonds with other carbon atoms.
They must be non-toxic ie not chemicals that could poison the customers because of the potential risk of contaminating things which can come into contact with the food like say cutting boards, dishes, utensils, pots, pans and any other similar items.