Answer:
Dmitry Mendeleev
Explanation:
Around 1869 a Russian scientist, Dmitry Mendeleev formed what is now known as the periodic table or chart. The Mendeleevian periodic table was based on the atomic weights of elements using the periodic law. The periodic law states that "chemical properties of elements are a periodic function of their atomic weights".
The modern periodic table was re-stated by Henry Moseley in the 1900s. He changed the basis of the periodic law to atomic masses.
Answer:
the HOMO-LUMO energy difference in ethylene is greater than that of cis,trans−1,3−cyclooctadiene
Explanation:
The λmax is the wavelength of maximum absorption. We could use it to calculate the HOMO-LUMO energy difference as follows:
For ethylene
E= hc/λ= 6.63×10^-34×3×10^8/170×10^-9= 1.17×10^-18J
For cis,trans−1,3−cyclooctadiene
E= hc/λ=6.63×10^-34×3×10^8/230×10^-9=8.6×10^-19J
Therefore, the HOMO-LUMO energy difference in ethylene is greater than that of cis,trans−1,3−cyclooctadiene
