题目

图中A-J是初中化学常见的化合物。A和B物质类别相同，只有C、F、G、H、I由两种元素组成，B、C中含有一种相同的元素，C可用作干燥剂，J是焙制糕点所用的发酵粉的主要成分之一，E和J分别与足量I反应的生成物相同。图中“—”表示两的物质间能发生化学反应;“→”表示物质间存在转化关系；部分反应物、生成物或反应条件已略去。 (1)写出化学式:J      ，B        。 (2)写出E→F反应的化学方程式                       。 (3)写出C与D 从方框中选择单词，带入短文空格内，使短文意思正确、通顺，再将其适当形式填入短文后的横线上。(每词限用一次)。 　　The verb“chat”means to talk(to someone)in a friendly, informal(非正式的)way．Today there are many 　　1　　 on the Internet where you can chat．You can chat with people all over the world, in many languages and about many subjects．These places are 　　2　　 called “chatroom”．Sometimes you need to register(注册)to enter a chatroom．This means that you need to provide a usename(用户名)and possibly your e-mail 　　3　　．Your username does not have to be your 　　4　　 name．It can be any name you want．When you have your username, other people in the chatroom will can you by that name and 　　5　　 else can use it． 　　Chatting is a good way to 　　6　　 your informal English, Messages in a chatroom are usually short sentences．Sometimes 　　7　　 are not even sentences, 　　8　　 just a few words that are not really grammatically(语法)correct．It’s a typical way in which we 　　9　　 in a quick conversation with friends．To save time, people often use abbreviations like TTYL(talk to you later)or IDK(I don’t know)．So don’t go to a chatroom to practice “perfect”English．Go to a chatroom to practice informal English and find new 　　10　　．You can even use a chatroom to help improve your typing skills if you want． 1．________ 2．________ 3．________ 4．________ 5．________ 6．________ 7．________ 8．________ 9．________ 10．________