As he began to teach inorganic chemistry, Mendeleev could not find a textbook that met his needs. Since he had already published a textbook on organic chemistry in 1861 that had been awarded the prestigious Demidov Prize, he set out to write another one. The result was Osnovy khimii (1868–71; The Principles of Chemistry), which became a classic, running through many editions and many translations. When Mendeleev began to compose the chapter on the halogen elements (chlorine and its analogs) at the end of the first volume, he compared the properties of this group of elements to those of the group of alkali metals such as sodium. Within these two groups of dissimilar elements, he discovered similarities in the progression of atomic weights, and he wondered if other groups of elements exhibited similar properties. After studying the alkaline earths, Mendeleev established that the order of atomic weights could be used not only to arrange the elements within each group but also to arrange the groups themselves. Thus, in his effort to make sense of the extensive knowledge that already existed of the chemical and physical properties of the chemical elements and their compounds, Mendeleev discovered the periodic law.
Pv =nRT
T= 273
n = 0.500
v= 11.2
R= 0.08206
p= 0.5×0.08206×273 ÷ (11.2) =10.00
Answer:
a) The structure of anthracene is planar with all the pi electrons delocalized in the structure to maintain aromaticity.
b) The C-C bond length in anthracene is about 140 pm with all the bond lengths being similar to each other.
The standard C-C bond length is 154 pm while standard C=C bond is about 134 pm. Therefore the bond length in anthracene is smaller than standard C-C bond length and longer than standard C=C bond length. This can be explained from the fact that the C-C bonds in anthracene has be mixed characteristics of single and double bond because of the delocalization of pi electrons over the whole structure. As a result, they are neither fully single nor fully double bond in nature. Hence the observed bond lengths.
c) This molecule is not flat. The N-atom is sp3 hybridized here and the H-atom attached to N will remain out of plane.
Explanation:
The greatest amount of energy released per gram of reactants occurs during a (1) redox reaction, although it should be noted that there are exceptions depending on environment.
