Periodic Table:In a periodic table, the horizontal rows are named as periods and the vertical columns are named as groups. These rows and columns have made the study of different existing elements very easy.Answer and Explanation: In the arrangement of elements existing in the periodic table, ...
Answer and Explanation:1 Mendeleev's periodic table was rejected because he was unable to tell the location of a hydrogen atom in the periodic table. Also, when we move from...
Janssen recorded the helium spectral line during the solar eclipse of 1868, while Lockyer observed it from Britain. Lockyer was the first to propose that the line was due to a new element, which he named. The formal discovery of the element was made in 1895 by chemists Sir William Ramsay,...
What formal term is applied to (a) the horizontal rows of the periodic table, and (b) the vertical columns? Why are chemists so interested in the number of valence electrons in atoms? Which pair of elements do you expect to be most similar? Why? a)...
Why do chemists classify reactions? Why is there no pop of pure oxygen and pure hydrogen? Why does helium exhibit more emission lines than hydrogen? Explain why group 1 are stored in paraffin and give examples. Why can't we use gas chromatography to analyze the sample of Steroids?
When industrial chemists want to make chlorine and lye through electrolysis, why can't they use electrodes made of common metals, such as silver or iron, or zinc? Why is the periodic table organized the way it is? Explain why the exact size of an atom is difficult to determine. ...
Why do chemists classify reactions? Explain why ethane does not react with HX (X = Cl, Br or I) under normal conditions. Why is iodine able to form the largest variety of interhalogen compounds? Why is dicinnamalacetone soluble in toluene and not ethanol?
Why do chemists and physicists say that matter is never destroyed, only transformed into another form? Why is carbon so important to living organisms? Why do topoisomerase inhibitors (camptothecins, for example) work well as anti-cancer agents? Why does carbon fixation require energy? What does ...
How do valence electrons determine chemical reactivity? Why are chemists so interested in the number of valence electrons in atoms? Explain its significance. How does electron affinity vary in the periodic table across a row in general? Explain your answer in terms of atomic number ...
What are coordination complexes and how do they form? Why does ethylene have a planar geometry? Explain why the following compound is an achiral compound. Discuss why we see an increase in boiling point with larger alkane molecules What is the reason that chemists categories Fe, Co and N...