Whichever one has a negative enthalpy value.
Normally in a mine the ore thats extracteed is unpure and contains many impurities and so are usually compounds and so must be then processed to form pure elements
some elements can be extracted from a solution of its ions such as magnesium
hope that helps
<h2>Answer:</h2>
They would be arranged in a trigonal planar orientation.
<h3>Explanation:</h3>
If there were only three electron groups around an atom they tend to repel each other and gain a trigonal planar orientation. A molecule with three electron groups orients the three groups as far apart as possible. They adopt the positions of an equilateral triangle 120° apart and in a plane. The shape of such molecules is trigonal planar. An example is BF3:
Answer:
Substances with high boiling points condense at the bottom and substances with lower boiling points condense on the way to the top. The crude oil is evaporated and its vapours condense at different temperatures in the fractionating column.
Explanation:
answer above
