问题 问答题

滴定管读数应遵守下列规则?

答案

参考答案:

(1)注入溶液或放出溶液后,需等待30s--1min后才能读数

(2)滴定管应垂直地夹在滴定台上读数或用两手指拿住滴定管的上端使其垂直后读数

(3)对于无色溶液或浅色溶液,应读弯月面下缘实际的最低点,对于有色溶液,应使视线与液面两侧的最高点相切,初读和终读应用同一标准.

选择题
阅读理解

The $11 billion self-help industry is built on the idea that you should turn negative thoughts like “I never do anything right” into positive ones like “I can succeed”. But was positive thinking advocate Norman Vincent Peale right? Is there power in positive thinking?

Researchers in Canada just published a study in the journal Psychological Science that says trying to get people to think more positively can actually have the opposite effect: it can simply highlight how unhappy they are.

The study's authors, Joanne Wood and John Lee of the University of Waterloo and Elaine Perunovic of the University of New Brunswick, begin by citing (引证) older research showing that when people get feedback which they believe is overly positive, they actually feel worse, not better. If you tell your friend who is slow to learn that he has the potential of an Einstein, you’re just underlining his faults. In one 1990s experiment, a team including psychologist Joel Cooper of Princeton asked participants to write essays against funding for the disabled. When the essayists were later praised for their sympathy, they felt even worse about what they had written.

In this experiment, Wood, Lee and Perunovic measured 68 students’ self-esteem (自尊). The participants were then asked to write down their thoughts and feelings for four minutes. Every 15 seconds, one group of students heard a bell. When it rang, they were supposed to tell themselves, “I am lovable.”

Those with low self-esteem didn’t feel better after the forced self-affirmation (自我肯定). In fact, their moods turned significantly darker than those of members of the control group, who weren’t urged to think of positive thoughts.

The paper provides support for newer forms of psychotherapy (心理治疗) that urge people to accept their negative thoughts and feelings rather than fight them. In the fighting, we not only often fail but can make things worse. Meditation (静思) techniques, in contrast, can teach people to put their shortcomings into a larger, more realistic viewpoint. Call it the power of negative thinking. 

小题1:The first paragraph is written _________.

A.to raise an argument about positive thinking

B.to introduce the power of positive thinking

C.to encourage people to have positive thoughts

D.to introduce the $11 billion self-help industry小题2:According to the study of the Canadian researchers, _________.

A.positive thinking is not as powerful as negative thinking

B.encouraging positive thinking may actually discourage people

C.happy people can think positively while unhappy people can’t

D.getting people to think positively can strengthen their confidence小题3:What does the underlined sentence in Paragraph 3 mean?

A.You are pointing out the mistakes he has made.

B.You are reminding him that he is not intelligent.

C.You are not taking his mistakes seriously enough.

D.You are showing he has great potential in spite of faults.小题4:We can learn from the last paragraph that _________.

A.negative feelings must be got rid of

B.there’s no point in thinking positively

C.it doesn’t make sense to think negatively

D.negative thinking is not always negative