Answer:
A. Mafic; iron and/or magnesium
Explanation:
Let's find the answer by naming some minerals and their chemistry.
Mafic minerals are dark-colored whereas felsic minerals are light-colored, thats way mafic rocks are dark-colored because they are mainly composed by mafic minerals and the other way around for felsic rocks.
But remember that mafic minerals as amphiboles, pyroxenes or biotites, involve in their chemical structure iron and/or magnesium. Although calcium and sodium can be incorporated in amphiboles and clinopyroxenes, they are not involved in orthopyroxenes and biotites. On the other hand, although potassium is involved in biotite and in some extent in amphiboles, this element is not involved in pyroxenes.
So in conclusion, mafic minerals are usually dark-colored because they involve iron and/or magnesium in their chemical structures.
Answer:
When an electron absorbs energy, it will move up from a lower energy level to a higher energy level, called the "excited state" of the negatively-charged subatomic particle.
The answer is <span>D. Nonvascular plants. These plants are usually very short and can't grow to be very tall. A good example is moss.
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Explanation:
A cation is a positively charged ion.
An anion is a negatively charged ion.
- In a cation, electrons are usually lost
- In an anion, electrons are usually gained.
In an atom, the balance between the number of protons and electrons determine whether they become an anion or cation.
Protons are positively charged particles.
Electrons are negatively charged
When an atom gains electrons, the number of electrons becomes more than that of protons. This leaves a net negative charge on the atom and it makes an anion.
When an atom loses electrons, the number of protons becomes more than that of electrons. This leaves a net positive charge on the atom and makes a cation.