Tính năng lượng liên kết O – H trong phân tử H2O, biết các dữ kiện sau: H2O(l) → H2O(k) ; H1 = 40,6 kJ/mol
2H
(k) → H2 (k) ; H2 = – 435 kJ/mol

Which of the following statements is false regarding aromaticity? a. the compound must be cyclic b. the compound must be fully conjugated c. the compound must be planar d.the number of electrons in the pi system must satisfy the hückel 4n+2 rule e. the compound must have a neutral charge

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.