4. 4 C + S8 = 4 CS2
5. H2 + O2 = H2O2 is already balanced.
6. 4 Na + O2 = 2 Na2O
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.
Those are types of water on a pH scale 7.0 and above are alkili water and anything under that is acidic
Answer:
The rabbit population will reach 500 after 10 months.
Explanation:
According to the given data:
The initial number of rabbit's equals 2.
Number of rabbit's after 2 months =2x3= 6
Number of rabbit's after 4 months = 6x3=18
Number of rabbit's after 6 months = 18x3=54
Number of rabbit's after 8 months = 54x3=162
Thus we can see that the number of rabbit's form a Geometric series with common ratio =3 and initial term = 2
Now the general term of a geometric series with first term 'a' and common ratio 'r' is given by

Thus we need to find when the term becomes 500 thus using the given data we have

Thus the fifth term (excluding the start term) will have a rabbit count of 500 now since each term has a time difference of 2 months thus sixth term will occur after 
The elements toward the bottom left corner of the periodic table are the metals that are the most active in the sense of being the most reactive. Lithium, sodium, and potassium all react with water, for example.