问题 填空题

根据所学化学反应原理填空:

(1)升高温度时,水的pH______(填“增大”“减小”或“不变”)

(2)体积、pH均相同的盐酸和醋酸溶液,中和等浓度的NaOH溶液时所需体积分别为V1、V2.则V1______V2(填“<”、“>”或“=”)

(3)某反应放热且熵增加,该反应______自发进行(用“能”或“不能”表示)

答案

(1)水的电离是吸热反应,温度升高促进了水的电离,溶液中氢离子浓度增大,溶液pH减小,

故答案为:减小;

(2)体积、pH均相同的盐酸和醋酸溶液,由于醋酸部分电离,醋酸浓度大于溶液中氢离子浓度,所以中和等浓度的NaOH溶液,消耗的醋酸溶液的体积小于消耗的盐酸溶液的体积,即V1<V2

故答案为:<;

(3)熵增加且放热反应,则△S>0,△H<0,所以△H-T△S<0,该反应能够自发进行,

故答案为:能.

阅读理解

阅读理解。

     Rock climbing(攀岩) did not become a sport until late in the 1900s. But now it has become a

popular outdoor activity. While rock climbing may still be necessary for mountain climbing, most

people just climb low mountains for fun.

     If you have ever done rock climbing, you will know that it is not a very easy sport. Indoor and

outdoor rock climbing both need practice. What most people don't know is that rock climbing is

one of the sports that depend on your body and mind(意志).

     To climb successfully, one must use wonderful skills(技能). One of the important rules is to

always have three parts of your body on the rock face. Another important rule is that your arms

only hold you close to the rock face while your legs are pushing(推) you up, the closer you are to

the rock face, the easier it is to climb.

     Rock climbing is a wonderful sport. Once you start to learn how to climb, you'll find more fun.

People who like games such as chess playing or problem-solving may love rock climbing, because

they are nearly the same in the way of thinking. For anyone who wants to get into beautiful shape

(体形), rock climbing is a fun and good way. Anyone who enjoys a difficult game and loves the

outdoors should think of taking rock climbing as a new hobby. 

1. When did rock climbing become a sport?

A. In 1900.

B. Early in the 1900s.

C. In the middle of the 1900s.

D. Late in the 1900s. 

2. The chess players may like rock climbing because _____. 

A. they'd like to get into beautiful shape

B. it is more interesting than chess playing

C. it is like chess playing in the way of thinking

D. they really tike to do sports 

3. What can we learn from the passage? 

A. Rock climbing is a kind of indoor and outdoor activity.

B. Rock climbing is a very easy sport.

C. When you climb, your arms push you up.

D. The closer you are to the rock face, the more difficult it is to climb.

问答题 简答题