A. Sodium is correct.
Sodium is an alkali metal.
Aluminum is a post-transitional metal- still a metal but it’s character is not as metallic as sodium.
Silicon is a metalloid- it has characteristics from both the metals and the non-metals.
Phosphorous is a non-metal.
They are examples of physical<span> contaminants .</span>
It tells you how many protons it has and because the number of protons =electrons it tells you also the number of electrons.
Answer:There are total 118 elements in world as about marbale
Explanation: