To help, I drew a diagram. This represents an ionic bond between Na and Cl. Na is giving his single electron to Cl, which is indicated by the arrow, to make Cl full with 8 electrons.
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.
The molarity of KBr solution is 1.556 M
molarity is defined as the number of moles of solute in volume of 1 L solution.
the number of KBr moles in 1 L - 1.556 mol
Therefore in 200.0 L - 1.556 mol/L x 200.0 L = 311.2 mol
Molar mass of KBr - 119 g/mol
mass of Kbr - 311.2 mol x 119 g/mol = 37 033 g
mass of solute therefore is 37.033 kg
Answer:
3-methylthiophene > thiophene > benzene > 2-methylfuran
Explanation:
Primarily, five membered heterocyclic aromatic rings undergo nitration at carbon-2. This is because, nitration at carbon-2 leads to the formation of three resonance structures while attack at carbon-3 yields only two resonance structures, hence it is less stabilized.
The presence of a methyl group which donates electrons promotes the stabilization of the cation formed in the nitration of 3-methylthiophene.
2-methylfuran is the least reactive towards nitration because the 2-position has been blocked by a methyl group.
