17. 下圖中A是制取溴苯的實(shí)驗(yàn)裝置,B、C是改進(jìn)后的裝置.請(qǐng)仔細(xì)分析,對(duì)比三個(gè)裝置,回答以下問(wèn)題：
（1）寫出三個(gè)裝置中所共同發(fā)生的兩個(gè)反應(yīng)的化學(xué)方程式：________________________________________________
`________________________________________________________________________________________________________________________________________________.
寫出B的試管中所發(fā)生反應(yīng)的化學(xué)方程式________________________________________________________________________.
（2）裝置A和C均采用了長(zhǎng)玻璃導(dǎo)管,其作用是________________________________________________________________________.
（3）在按裝置B、C裝好儀器及藥品后要使反應(yīng)開(kāi)始,應(yīng)對(duì)裝置B進(jìn)行的操作是________________
________________________________________________________________________________________________________________________________________________；應(yīng)對(duì)裝置C進(jìn)行的操作是________________________________________________________________________________________________________.
（4）裝置B、C較好地解決了A中加裝藥品和使裝置及時(shí)密封的矛盾,方便了操作.A裝置中這一問(wèn)題在實(shí)驗(yàn)中造成的后果是________________________________________________________________________________.
（5）B中采用了洗氣瓶吸收裝置,其作用是________________________________________________________________________________,反應(yīng)后洗氣瓶中可能出現(xiàn)的現(xiàn)象是________________________________________________________________________________________.
（6）B裝置也存在兩個(gè)明顯的缺點(diǎn),使實(shí)驗(yàn)的效果不好或不能正常進(jìn)行.這兩個(gè)缺點(diǎn)是：
________________________________________________________________________________________________________________________________________________.