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.
It's 2, glass. Water, nitrogen, and sucrose don;t have a crystalline structure.
Answer: Cu
Explanation: It is Cu because the origin of the word Copper comes from the latin word "Cuprum".
Isomers are the compounds having same molecular formula but different structural formula.
Since, molecular formula is isomers are same, they have same mass.
Now, <span>methyl ethanoate is an isomer of propanoic acid, hence they have same mass.
</span>∴ Molecular mass of propanoic acid = 74.1 amu or 74.1 g/mol<span>
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