题目内容

Choose the right characterization ()

A. Group 2 elements are called "alkali metals".
B. Graphite is one of the hardest known materials.
C. Lithium is a Group 1 element containing just a single valence electron.
D. Helium gas is diatomic gas.

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添加电解质不利于凝胶形成。( )

单链憎水基和较大极性基的分子或离子容易形成球状胶束。( )

选出下列不可用化学气相沉积来制备的化学反应()

A. Fe(C5H5)2=Fe+5C+5H2
B. Si(OC2H5)4+2H2O=SiO2+4C2H5OH
CH4=C(金刚石)+2H2
D. Ni(CO)4=Ni+4CO

影响溶胶-凝胶制备过程的因素有() ①pH②温度③加料顺序④搅拌速度⑤溶剂极性

A. ①④⑤
B. ①②③④⑤
C. ③④⑤
D. ②③④