问题 问答题

下图转化关系,A、B、C、D、E都是常见元素的单质,在常温常压下A是固体,其余都是气体,且C呈黄绿色.化合物H和I两种气体相遇时产生白烟.化合物G的焰色反应为黄色.反应①利②均在溶液中进行.请按要求问答下列问题:

(1)写出下列物质的化学式:D______、F______.

(2)反应①的离子方程式为______.

(3)检验K溶液中阴离子的试剂是______.

(4)实验室制取I的化学方程式为______.

(5)向J溶液中滴入NaOH溶液时,生成的白色沉淀迅速变成灰绿色,最后变成红褐色.写出沉淀由白色变成红褐色的化学方程式______.

答案

A、B、C、D、E都是常见元素的单质,C呈黄绿色,则C为Cl2,化合物H和I两种气体相遇时产生白烟,则H为HCl,I为NH3,D为H2,E为N2,K为NH4Cl,J为FeCl2,化合物G的焰色反应为黄色,与盐酸反应生成二氧化碳气体,且F与二氧化碳反应生成G,F由两种单质反应生成,所以A为Na,B为O2,F为Na2O2,则G为Na2CO3

(1)由上述推断可知,D为H2,F为Na2O2,故答案为:H2;Na2O2

(2)反应①为CO32-+2H+═CO2↑+H2O,故答案为:CO32-+2H+═CO2↑+H2O;

(3)K溶液中阴离子为Cl-,加硝酸酸化的硝酸银溶液,生成白色沉淀,则说明含有Cl-

故答案为:硝酸酸化的硝酸银溶液;

(4)I为NH3,实验室利用氯化铵与碱石灰共热来制取,该反应为2NH4Cl+Ca(OH)2

.
CaCl2+2NH3↑+2H2O,

故答案为:2NH4Cl+Ca(OH)2

.
CaCl2+2NH3↑+2H2O;

(5)向J溶液中滴入NaOH溶液时,生成的白色沉淀迅速变成灰绿色,最后变成红褐色,

该反应为4Fe(OH)2+O2+2H2O═4Fe(OH)2,故答案为:4Fe(OH)2+O2+2H2O═4Fe(OH)2

阅读理解

阅读理解。

     When people visit Switzerland for the first time, they look with great interest, not only at the mountains

but also at a type of clock-a Cuckoo-clock, on sale there. Cuckoo-clocks are very popular with tourists

looking for a souvenir. A Cuckoo-clock has a small painted cuckoo that comes out near the top of the clock

every half an hour and says, "Cuckoo". Every hour it comes out and says "Cuckoo" the right number of times.

It does not get a sore throat at midnight or mid-day! Children find these clocks wonderful. Adults gradually

get annoyed because the cuckoo never misses an hour or a half hour, and this makes a short sleep in an

armchair rather difficult.

     In Europe, the cuckoo's call is a welcome sign that summer is on the way. This is the time when the

mother cuckoo flies round, looking for a nest (巢) to lay one of her eggs. She chooses a nest belonging to

another bird which already has eggs. When the nest is left unnoticed for a minute or two, the cuckoo rushes

down, lays an egg and hurries off. In this way, she may lay her eggs in as many as four different nests. not

one of which has been built by herself. 

     When a cuckoo egg hatches (孵化), the baby bird is bigger and stronger than the other nestlings. Step by

step, it pushes other baby birds and any unhatched eggs out of the nest. In this way, it receives all the food

from its foster-parents (养父母) and has a better chance of surviving.

1. When tourists first visit Switzerland, _____.

A. they are impressed by the mountains

B. they do not find the mountains interesting

C. the Cuckoo-clocks are more interesting to them than the mountains are

D. they find neither the mountains nor the clocks interesting

2. Which of the followings is NOT true?

A. Cuckoos often lay eggs in other birds' nests.

B. If it's exactly 12 o'clock now, the cuckoo will say "cuckoo" twelve times.

C. The cuckoo does not say"cuckoo" at midnight and mid-day.

D. The adults don't like the Cuckoo-clocks as much as the children.

3. Tourists like to buy Cuckoo-clocks _____.

A. to remind them of a visit

B. because they can tell time exactly

C. to amuse their children

D. because they are cheaper than other clocks

4. Why are Europeans happy to hear the call of the cuckoo?

A. They like to catch and eat this large bird.

B. The bird has a beautiful way of singing.

C. This bird is used to tell the time in Switzerland.

D. It makes them think that warmer weather is coming.

5. What may other birds think when a cuckoo lays an egg in their nest?

A. They push it out of their nest.

B. It seems that they don't know what has happened.

C. They don't like it but cannot do anything about it.

D. They welcome the egg and the young cuckoo.

单项选择题