问题 推断题

A、B、C、D、E是五种短周期元素。已知:它们的原子序数依次增大,A是元素周期表中原子半径最小的元素;B原子最外层电子数比其次外层电子数多2,C是E的邻族元素;D和E的原子序数之和为30,且D的族序数与周期数相等。甲、乙、  丙、丁是它们两两形成的化合物,其中甲分子中含有18个电子。

物质组成  甲  乙  丙  丁
化合物中各元素

原子个数比

 A和C

1:1

 B和A

1:4

 D和E

1:3

  B和E

1:4

请回答下列问题:

⑴C的氢化物与乙相比较,稳定性强弱关系(用相应的化学式表示):_____>_  __

⑵元素E在周期表中的位置为第          周期           族;

⑶请写出两种与乙具有相同电子数的非单核离子的化学式:_____和_____;

⑷把D的单质放到NaOH溶液中,反应的化学方程式为:______________________;

⑸写出甲的电子式:________________;

⑹有200mL MgCl2和丙的混合溶液,其中c(Mg2)= 0.2 mol· L-1,c(Cl)= 1.3mol·L-1,要使Mg2全部转化为沉淀分离出来,至少需要4 mol·L-1 NaOH 溶液的体积是: __  ___

答案

⑴ H2O>CH4 ⑵第三周期VIIA族

⑶NH4+和OH-  (其他合理答案也可)(2分)

⑷2Al+ 2NaOH+6H2O  =  2Na[Al(OH)4]+3H2

⑹80 mL

题目分析:依据题意可以知道,A、B、C、D、E分别为H、C、O、Al、Cl,所以⑴中,C的氢化物为H2O,乙为CH4,故其稳定性强弱关系为H2O>CH4;⑵E为Cl,在周期表中的位置为第三周期VIIA族;⑶乙为CH4与乙具有相同电子数的非单核离子的化学式为NH4+和OH-;⑷D的单质为铝,其与NaOH溶液的反应为2Al+ 2NaOH+6H2O  =  2Na[Al(OH)4]+3H2↑;⑸甲为过氧化氢,其电子式为;⑹丙为AlCl3,因为c(Mg2)= 0.2 mol· L-1,c(Cl)= 1.3mol·L-1,所以 MgCl2的浓度为0.2 mol· L-1,即有0.04mol,AlCl3的浓度为0.3mol· L-1,即有0.06mol,当要使Mg2全部转化为沉淀分离出来,即要把铝离子全部转化为偏铝酸根离子,即发生

Al3+4OH=AlO2+2H2O,消耗的 NaOH 溶液为0.24mol,将Mg2全部转化为沉淀,即发生

Mg2+2OH=Mg(OH)2↓,消耗的 NaOH 溶液为0.08mol,所以总共需要 NaOH 溶液0.08+0.24=0.32mol,所以0.32/4L=0.08L,即80 mL。

点评:本题考查了元素及相关化合物的性质、简单化学计算,属于高考的基础考点,本题具有一定的综合性,但是总体难度适中。

阅读理解

阅读理解。

     Food sometimes gets poisoned with harmful things. A person who eats such food can get an illness called

food poisoning. Food poisoning is usually not serious, but some types are deadly, The symptoms of food

poisoning usually begin within hours of eating the poisoned food. Fever is one of the most common symptoms.

     Certain microorganisms (微生物) cause most types of food poisoning. Bacteria and other microorganisms

can poison eggs, meat, vegetables, and many other foods. After entering the body, these tiny living things

release (释放) poisons that make people sick.

     Some chemicals can also cause food poisoning. They are often added to food while it is being grown,

processed, or prepaid. For example, many farmers spray chemicals on crops to kill weeds and insects. Some

people may have a bad reaction to those chemicals when they eat the crops.

     Some plants and animals contain natural poisons that are harmful to people. These include certain kinds of

seafood, grains, nuts, seeds, beans, and mushrooms.

     When people handle food properly, the risk of food poisoning is very small Microorganisms multiply rapidly

in dirty places and in warm temperatures. This means that people should never touch food with ditty hands or

put food on unwashed surfaces. Food should be kept in a refrigerator to stop microorganisms from gnawing.

Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food

covered with chemicals before eating it. Finally, people should not eat raid mushrooms or other foods that grow

in the wild. Some of these foods may contain natural materials that are poisonous to humans. In addition, some

types of fish can be poisonous.

     Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat

natural poisons, they must go to the hospital right away to have their stomachs emptied.

1. Which of the following statements is NOT true?

A. Food when poisoned can make people sick.

B. Food poisoning means death.

C. Food poisoning comes in varieties.

D. Food poisoning can be serious.

2. We know from the passage that the symptoms of food poisoning _____.

A. are always accompanied by a fever

B. are too common to be noted

C. can be noticed within hours

D. can be ignored

3. Food poisoning can be caused by all the following EXCEPT _____.

A. some chemicals

B. low temperatures

C. some tiny living things

D. certain natural materials

4. From Paragraph 5, we can learn that _____.

A. mushrooms should not be eaten

B. vegetables are safer than meat and seafood

C. natural poisons are more dangerous than chemicals

D. different types of food should be handled differently

5. It can be inferred from the passage that _____.

A. natural materials are safe in food processing

B. chemicals are needed in food processing

C. food poisoning can be kept under control

D. food poisoning is out of control

单项选择题