<span>Welding in confined spaces or on stainless steel generates (B) Hexavalent Chromium a very toxic chemical. Hexavalent chromium are chemical compounds that has a chromium with an oxidation state of +6. It is commonly used in textile dyes and wood preservation to avoid corrosion and conversion coatings.</span>
The first one is 2
The second is 1
The third is 6
And the fourth is 3
People who make medicine.
It is a chemical change
.
Answer:
16
Explanation:
Group two elements are alkaline earth metal.
All these have two valance electrons. In order to achieve noble gas configuration it loses its two valance and get complete octet.
Reaction with group 16.
Reaction with oxygen,
They react with oxygen and form oxide.
2Ba + O₂ → 2BaO
2Mg + O₂ → 2MgO
2Ca + O₂ → 2CaO
this oxide form hydroxide when react with water,
BaO + H₂O → Ba(OH)₂
MgO + H₂O → Mg(OH)₂
CaO + H₂O → Ca(OH)₂
With sulfur,
Mg + S → MgS
Ca + S → CaS
Ba + S → BaS
