问题 填空题

((2)题每空3分,其余每空2分,共12分)A、B、C、D均为中学化学常见的物质,它们之间的反应关系如下图:

回答下列问题:

(1)若A是可溶性的强碱,B是酸式盐,D不溶于稀硝酸,则B的化学式为________________,有关的离子方程式为___________________________________    

(2)若B是正盐,D既可溶于盐酸又可溶于NaOH溶液。

①若C为能使澄清石灰水变浑浊的无色无味气体,该反应的离子方程式为

____________________________________________________                       。 

②若A是一种淡黄色固体,且A与B以物质的量之比3∶1混合时,推知B的化学式为

_________              _。

(3)若B为Ca(HCO3)2溶液,A与B的溶液反应时只生成气体C、CaCO3和水,则A的化学式为__________________       。

答案

((2)题每空3分,其余每空2分,共12分)

(1)NH4HSO4(2分) NH4+ + H+ + SO42- + Ba2+ + 2OH- = NH3↑+2H2O+BaSO4↓(3分)

(2)① 3CO32- + 2Al3+ + 6H2O = 3CO2↑+ 2Al(OH)3

或 3HCO3+ Al3+ ="=" 3CO2↑+ Al(OH)3↓ (3分)② Al2(SO4)3(2分);(3)CaC2(2分)

(1)D不溶于稀硝酸,则D时硫酸钡或氯化银。A是可溶性的强碱,B是酸式盐,且反应中生成气体,则气体一定氨气,即A是氢氧化钡,B是硫酸氢铵,方程式为NH4+ + H+ + SO42- + Ba2+ + 2OH- = NH3↑+2H2O+BaSO4↓。

(2)D既可溶于盐酸又可溶于NaOH溶液,则D是氢氧化铝。

①C为能使澄清石灰水变浑浊的无色无味气体,则C是CO2,所以方程式为3CO32- + 2Al3+ + 6H2O = 3CO2↑+ 2Al(OH)3↓,或 3HCO3+ Al3+ ="=" 3CO2↑+ Al(OH)3↓。

②A是一种淡黄色固体,则A是过氧化钠。A与B以物质的量之比3∶1混合,说明B中含有2个铝离子,所以B是硫酸铝。

(3)由于反应中生成碳酸钙沉淀,所以产生的气体应该是A和水反应生成的,所以根据原子守恒可知,A是CaC2。CaC2溶于水生成乙炔和氢氧化钙,氢氧化钙和碳酸氢钙反应生成碳酸钙和水。

阅读理解

阅读理解。

     In the doctor's waiting room, sick people are waiting on their chair. Bob, a school boy, is among them.

They all look very sad except (除了) Bob. He is enjoying an exciting story in a magazine. Just then the

 doctor comes in to say he is ready for the next person. Bob jumps up and runs into the doctor's room.

     "What's your trouble?" says the doctor. Before Bob could say a word, the doctor makes him lie down

 on a bed,  "Now, let me listen to your heart." Bob tries to speak, but the doctor tells him not to say

 anything. "I'll take your temperature." Bob tries to sit up, but the doctor stops him. After a moment, the

 doctor says, "Well, boy, you don't have a fever. In fact, there's nothing wrong with you."

     "I know there isn't," says Bob. "I just come here to get some medicine for my father."

1. Bob sits in the waiting room to_____.

    A. see the doctor

    B. wait for the doctor

    C. read his magazine

    D. buy some medicine

2. All the sick people look sad except Bob because _____.

    A. Bob is too young to (太小了而不会) worry about anything

    B. his father isn't very ill

    C. he is interested in the magazine

    D. there is nothing wrong with him

3. From the passage we can see that _____.

    A. the doctor is careless

    B. there is no nurse in the doctor's room

    C. the doctor is warm-heart

    D. the doctor takes Bob as (把Bob当作) a sick person

4. While looking over Bob, the doctor might think that_____.

    A. Bob is funny

    B. Bob isn't naughty (淘气的)

    C. Bob is foolish

    D. Bob is very ill

5. When Bob tells the doctor what he is here for, the doctor might think that _____.

    A. he himself is funny

    B. he himself is careless

    C. he himself is foolish

    D. he himself is naughty

问答题 简答题