问题 选择题

下列的图示与对应的叙述相符的是(    )

       

A.图1表示KNO3的溶解度曲线,图中a点表示的溶液通过升温可以得到b点

B.图2表示某一放热反应,若使用催化剂E1、E2、ΔH都会发生改变

C.图3表示向Na2CO3和NaHCO3的混合溶液中滴加稀盐酸时,产生CO2的情况

D.图4表示向100mL0.1mol /L的AlCl3和0.1mol/L的NH4Cl混合溶液中滴加1mol/L的NaOH溶液时n(Al3+)和n(AlO2-)的变化情况

答案

答案:D

题目分析:A、a点到b点,为恒温,故可以通过加入溶质来实现,错误;B、催化剂能改变活化能,但不能改变反应热,错误;C、Na2CO3与盐酸反应分两步,两步消耗盐酸之比为1:1,又因有NaHCO3,故第二步消耗的盐酸多于第一步,错误;D、反应的先后顺序为①Al3+→Al(OH)3,②NH4+→NH3·H2O,③Al(OH)3→AlO2-,正确。

阅读理解

Howling is a behavior commonly observed among a wolf nark. An animals, wolves work together to hunt and rely on howling was an important means of communication each other. There are different explants of a wolf’s howl and it appears that there may be more to discover.      One theory is that wolves howl to bend better together. It’s almost as if howling together helps the pack stay together. Perhaps something similar to people feeling a sense of involvement with each other when singing a song together . But this theory may be wrong, explains Fred H. Harington, a professor who studies wolf behavior.     Indeed, there have been tines when wolves have been seen one moment howling in a exhorts, and the next, quarreling anions each other. It appears that usually the lowest-tanking menthes of the pack may actually be “punished” for

Joining in the churs at times. So is howling a way to strcagthen a social boad or just a way to reconfirm status among its members? ——Why do welves howl for sure?

What is cleat, however, is that howling is often used among packmates to locate each other. Hunting grounds are distant and it happens that woloves may separate from one another at times. When this happens, howling appcars to be an ercellent means of gathering.

Howling, interestingly, is a contagious behaviour. When one wolf starts to howl, very likely others will follow. This is often seen to occat in the morning, as if wolves were doing some sotr of “roll rall”where wolves all howl togeter to howl, very likely others will follow. This is often seen to occar in the morning, as if wolves were doing w some sotr of “roll call”where wolves all howl together to repotr their pteence.

小题1:.What the por similarity between wolves’ how humaes ting in chorus?

A.The act of calling each other.

B.the sense of accomplishment.

C.The act of hunting for something.

D.The sense of belonging to a group.小题2:.Why does Harrington think the“secial boad”theory may be wrong?

A.Wolves separate from each other after howling.

B.Wolves tend to protect their hunting grounds.

C.Wolves sometimes have quarrels after howling together.

D.Wolves of low rank are encouraged to join in the chorus.小题3:Reseatchers are sure that wolves often howl to______.

A.show their ranks

B.find their companion

C.report the missing ones

D.express their lonelingess小题4:“Howling… is a contagious behaviour”(in the last paragraph)means_ ______.

A.howling is a signal for hunting

B.howling is a way of communication

C.howling aften occurs in the morning

D.howling spreads from one to another

多项选择题