______ is a periodic 2 element containing just four valence electrons.
查看答案
______ is another allotrope of oxygen.
To overcome Ea and to perform a reaction, the following strategy is not the feasible ()
A. Heating reactant
B. Igniting reactant
C. Using catalyst
D. Increasing concentration of reactant
Choose the right name of 盐酸 and 硫酸 ()
A. Hydrochloric acid and hydrogen sulfate
B. Hydrogen chloride and hydrogen sulfate
C. Hydrochloric acid and sulfuric acid
D. Hydrogen chloride and sulfuric acid
Choose the right name of 乙烷 and 丁炔 ()
A. Ethane and butyne
B. Ethane and butayne
C. Ethene and butyne
D. Ethane and butane
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