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.
The statement that best describes the variables in a controlled experiment is independent variable while all other conditions are unchanged.
<h3>What is an experiment?</h3>
An experiment is a scientific research, findings or investigation about a subject matter with the aim of validating a claim and establishing theories.
A controlled experiment refers to an experiment in which the variables involved and the control factor are kept in the same group except for one variable which can be changed.
Therefore, The statement that best describes the variables in a controlled experiment is independent variable while all other conditions are unchanged.
Learn more about experiment below.
brainly.com/question/25303029
#SPJ1
Im not sure what it is but i will try
BaCl₂(aq) + Na₂SO₄(aq) = BaSO₄(s) + 2NaCl(aq)
Ba²⁺(aq) + 2Cl⁻(aq) + 2Na⁺(aq) + SO₄²⁻(aq) = BaSO₄(s) + 2Na⁺(aq) + 2Cl⁻(aq)
Ba²⁺(aq) + SO₄²⁻(aq)= BaSO₄(s)
Where are options? without that, i can’t help you sorry
Answer:
Explanation:
Density can be defined as mass divided by volume. But 2 objects made of the same material will have the same density regardless of their volume.
