I choose the letter c witch is density I believe that it’s useful for determining identifying relationships between substances
The answer is the plague, or the black death
In resonance structures, the chemical connectivity in the molecule is same but the distribution of electrons are different around the structure. They are created by moving electrons in double or triple bonds, and not atoms.
Phenol, 
and methanol, 
both are alcohols that contain an 
group attached to carbon atom.
Due to loss of 1 
from phenol, it forms phenoxide anion and due to presence of double bond in the benzene ring the negative charge on the oxygen atom (which represents electrons) will resonate with double bonds of benzene ring as shown in the image. The resonance-stabilized phenoxide ion is more stable. Whereas when methanol lose 1 it forms methoxide anion and there are no such electrons present in the structure of methoxide that will result in the movement of electron. Since, due to resonance-stabilized phenoxide ion is more stable than methoxide ion, so it is a stronger acid.
The structures of the anions resulting from loss of 1 from phenol and methanol is shown in the image.
The elements should be label as follows yellow = OH, blue = Fe, green = Ba, red = Cl
The mix between aqueous barium hydroxide and aqueous iron chloride leads to barium chloride and iron hydroxide. This reaction is shown below:
- Ba(OH)2 + FeCl3 → BaCl2 + Fe(OH)3
Moreover, in these products, the iron hydroxide will form a solid substance that precipitates in the bottom of the container, while the barium chloride is more likely to maintain its liquid state.
According to this, the substance in the bottom is the iron hydroxide or Fe (OH)2, and in this, the yellow dots represent the Hydroxide or OH, while the blue dots are the Iron considering there in iron hydroxide there are two molecules of OH for each molecule of iron.
On the other hand, at the top, there is the barium chloride or BaCl2. This means the green dots are the Barium and the red ones are the Chlorine as there should be more Chlorine particles than Barium ones
Learn more in: brainly.com/question/19595631
Explanation
There are three main branches of science: physical science, Earth science and life science. Let's talk about each branch and the areas of study within each branch. Physical science is the study of inanimate natural objects and the laws that govern them.
