3．(2010天津卷)下列鉴别方法可行的是

A．用氨水鉴别Al³⁺、Mg²⁺和Ag⁺

B．用Ba(NO₃)₂溶液鉴别Cl^－、SO和CO

C．用核磁共振氢谱鉴别1－溴丙烷和2－溴丙烷

D．用KMnO₄酸性溶液鉴别CH₃CH＝CHCH₂OH和CH₃CH₂CH₂CHO

解析：Al³⁺和Mg²⁺与氨水反应都只生成沉淀，不溶解，无法鉴别，故A错；SO₄^2-和CO₃^2-与Ba(NO₃)₂反应都生成白色沉淀，无法鉴别，故B错；1-溴丙烷有三种等效氢，其核磁共振谱有三个峰，而2-溴丙烷有两种等效氢原子，其核磁共振谱有两个峰，故可鉴别，C正确；碳碳双键、醛基都能被酸性KMnO₄氧化，KMnO₄溶液都退色，故无法鉴别。

答案：C

命题立意：考查阴阳离子和有机物的鉴别，通过鉴别，考查离子或有机物的化学性质。

5. 选A。这句话本意是说他不会跟随其他人，但跟文章主题音乐联系起来，以及根据前面一句话He is true to himself可知隐含意义为他有自己的音乐风格。

4. 选D。根据第5段中It makes him attractive to me可知答案。

3. 选C。根据第4段的His mother noticed the boy’s special interest in music 可知Chou小的时候就对音乐很感兴趣，也就是或那时就开始喜欢音乐了。

2. 选B。根据第2段中的His fans are so excited because he will sing songs in Beijing on September 12可知答案。

1. 选D。根据第5段中的Chou is not very handsome. 可知A不对；根据第1段中的He doesn’t smile very often可知B不对；根据第1段中的He is quiet and shy可知C也不对。故答案选D。

5. The sentence “He never follows others” in the last paragraph means _______.

A. he always has his own style(风格)　　 B. he likes to walk alone

C. he doesn’t like other people’s songs at all　　　 D. no one can catch up with him

[答案及解析]

4. According to one of his fans, Jay _______.

A. is a good student　　　　　　　　　　　　 B. has long and beautiful hair

C. is a well-known pianist　　　　　　　　 D. is very attractive to them

3. When he was a little child, he _______.

A. talked a lot every day　　　　　　　　　 　　　　　　　　　 B. did well in his study at school

C. started to like music　　　　　　　　　　 　　　　　　　　　　D. had huge crowds of fans

2. His fans are so excited because _______.

A. he released a new album in July　　　 　B. he will sing new songs in Beijing

C. he can play the piano very well　 D. his new album was named after his mother