Choose the right characterizations of oxygen () ①colourless ②odourless ③tasteless ④Liquid and solid oxygen are pale blue
A. ①②③④
B. ①④
C. ②③④
D. ①③
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Which is an excellent insulator even when molten or dissolved in water ()
A. Metallic Crystals
B. Ionic Crystals
C. Molecular Crystals
D. Atomic Crystals
The mathematical treatment of of () is particularly difficult to develop.
A. solid
B. liquid
C. gas
D. molten
K ion has an oxidation number of ()
A. +1
B. +2
C. 0
D. -1
Choose the right characterization of hydrogen()
A. 氢元素与氢原子表述为hydrogen,氢气的表述为bihydrogen。
B. 氢元素与氢原子表述为hydrogen,氢气的表述为dihydrogen。
C. 氢元素与氢原子表述为hydrogen,氢气的表述为hydrogens。
D. 氢元素、氢原子与氢气的表述都为hydrogen。
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