Answer: A) calcite
Explanation:
Hardness can be defined as the ability of the mineral to resist the scratch. It is the property to judge the hardness of the mineral. Mineralogist study this property of hardness using Mohs hardness scale.
Talc is the least hard substance after that gypsum, then calcite, fluorite, and then apatite.
The gypsum can be scratched by the calcite but the calcite cannot scratch apatite as it is softer than apatite.
Answer: Breathing through a mask decreases the amount of oxygen we need to live & be. The only potentially toxic molecule that you routinely exhale is carbon dioxide. Carbon dioxide would not be trapped by a mask.
Explanation:
<h3>Answer:</h3>
True
The sun is the primary source of energy
Answer:
boron aluminum gallium indium
Explanation:
hope this helps you
The correct answer is BI₃
Lewis acid refers to a compound that could accept a pair of electrons, while Lewis base refers to a compound that could donate a pair of electrons.
In the mentioned reaction,
In NH₃, nitrogen exhibits a lone pair of electrons and is functioning as a Lewis base. In BI₃, the boron is deficient for an electron pair, thus in order to complete its octet it functions as a Lewis acid.