Answer:
Compound A is succinic anhydride and B is methyl succinate (the monomethyl ester).
Structural Diagram is attached.
Explanation:
A.
Succinic anhydride appears as colorless needles or white crystalline solid. ... Succinic anhydride, also called dihydro-2, 5-furandione, is an organic compound with the molecular formula C4H4O3. It is the acid anhydride of succinic acid.
B.
Monomethyl succinate is a dicarboxylic acid monoester that is succinic acid in which one of the carboxy groups has been converted to its methyl ester. It is a dicarboxylic acid monoester and a hemisuccinate. ... They have the general structure RC(=O)OR', where R=fatty aliphatic tail or organyl group and R'=methyl group.
a) The change here is that metallic iron is converted into ions and copper is deposited. This is called a displacement reaction.
b) 
is oxidised in this reaction.
c)$ \mathrm{Fe_{(s)}+ CuSO_{4(aq)} \rightarrow FeSO_{4(aq)} + Cu_{(s)}}$
Answer:
The absorption and strength of the H-beta lines change with the temperature of the stellar surface, and because of this, one can find the temperature of the star from their absorption lines and strength. To better comprehend, let us look into the concept of the atom's atomic structure.
Atoms possess distinct energy levels and these levels of energy are constant, that is, the temperature has no influence on it. However, temperature possesses an influence on the electron numbers found within these levels of energy. Therefore, to generate an absorption line of hydrogen in the electromagnetic spectrum's visible band, the electrons are required to be present in the second energy level, that is when it captivates a photon.
Therefore, after captivating the photons the electrons jump from level 2 to level 4, which shows that there is an increase in the stellar surface temperature and at the same time one can witness a decline in the strength of the H-beta lines. In case, if the temperature of the surface increases too much, then one will witness no attachment of electron with the hydrogen atom and thus no H lines, and if the temperature of the surface becomes too low, then the electrons will stay in the ground state and no formation of H lines will take place in that condition too.
Hence, to generate a very robust H line, after captivating photons the majority of the electrons are required to stay in the second energy level.
The Atomic Number.
-Hope this helps!
