Answer:
D.
Explanation:
Water is polar, for one thing. Polar mixes with polar, nonpolar mixes wih nonpolar. This leaves D.
Answer:
10.the pauli exclusive principle statues that, in an atom
or molecules, no two electrons can have same four electronic quantum numbers.as an orbit can contain a maximum of only two electrons.the two electrons must have opposing spins
B. Biomass
(I guess so cause other ones are already being used)
Answer: 17) d. 
18. c. The empirical formula of a compound can be twice the molecular formula.
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
To calculate the molecular formula, we need to find the valency which is multiplied by each element to get the molecular formula.
The equation used to calculate the valency is:

The empirical mass can be calculated from empirical formula and molar mass must be known.
17. Thus the empirical formula of
should be 
18. The molecular formula will either be same as empirical formula or is a whole number multiple of empirical formula. Thus the empirical formula of a compound can never be twice the molecular formula.