22.Oxidation occurs when materials containing are exposed to oxygen and water

iron

Explanation:

iron reacts with oxygen easily causing rust to form. the haemoglobin in your red blood cells contains haem which is iron and that's how your body transfers oxygen all over

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.

pie chart because it is in percents ( % )