试题与答案

钢丝在室温下反复弯折,会越弯越硬,直接断裂,而铅丝在室温下反复弯折,则始终处于软态,

题型:单项选择题

题目:

钢丝在室温下反复弯折,会越弯越硬,直接断裂,而铅丝在室温下反复弯折,则始终处于软态,起原因是()。

A.Pb不发生冷变形强化,不发生再结晶,Fe发生冷变形强化,不发生再结晶

B.Fe不发生冷变形强化,不发生再结晶,Pb发生冷变形强化,不发生再结晶

C.Pb发生冷变形强化,发生再结晶,Fe发生冷变形强化,不发生再结晶

D.Fe发生冷变形强化,发生再结晶,Pb发生冷变形强化,不发生再结晶

答案:

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题型:填空题

(1)常温下,有A、B、C、D四种无色溶液,它们分别是CH3COONa溶液、NH4Cl溶液,盐酸和NaNO3溶液中的一种。已知A、B的水溶液中水的电离程度相同,A、C溶液的pH值相同。则:

①B是__________溶液,C是__________。

②常温下若B溶液中c(OH-)与C溶液中的c(H+)相同,B溶液的pH用PHb表示,C溶液的pH用pHc表示,则

pHb+pHc=__________(填某个数)。

(2)已知某溶液中只存在OH-、H+、NH4+、Cl-四种离子,某同学推测其离子浓度大小顺序有以下几种

①c(Cl-)>c(NH4+)>c(H+)>c(OH-) ②c(Cl-)>c(NH4+)>c(OH-)>c(H+)

③c(NH4+)>c(Cl-)>c(OH-)>c(H+) ④c(Cl-)>c(H+)>c(NH4+)>c(OH-)

则:

(Ⅰ)上述关系一定不正确的是__________(填序号)。

(Ⅱ)若溶液中只有一种溶质,则该溶液中离子浓度的大小关系为__________________(填序号)。

(Ⅲ)若四种离子浓度关系有c(NH4+)=c(Cl-),则该溶液显__________(填“酸性”、“碱性”或“中性”)。

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题型:阅读理解

C

We are just getting older and older with each New Year. Vigor and wisdom

are draining, and bit by bit we are moving away from the amazement of youth.

Yet neither fear nor anxiety helps retain youth. Instead, a few living habits

help maintain.

●Laugh to your heart's content as much as you can. Laughter helps reduce

pressure and improve your immune system, which makes people look 8 years younger.

●Keep an eye on your blood pressure. Those with a blood pressure of 115/75mmHg look 2.5 years younger than those above 160/90mmHg.

●Quit smoking and avoid passive smoking. This can take 8 years off your appearance.

●Spare some time for exercises each day. Exercises need not be tiring. A 20 minute walk every day makes people look 5 years younger.

●Keep learning and absorb something new each day. Speak the same language as the young people. Learning something every day makes people look 2.5 years younger.

●Keep other pressures under control. Too much pressure makes people look 30 years older. If they are good at networking and manage to keep pressure under control, they will look 30 years younger.

●Secure high quality medical care insurance and do whole body check regularly. For those contracted with chronicle diseases, proper treatment and qualification of the diseases makes people look 12 years younger than what they would without proper treatment.

63. The passage is mainly about _________.

A. the important of retaining youth    B. some tips helping people retain youth

C. moving away from the amazement of youth

D. the connections between the health and the age

64. The underlined sentence “This can take 8 years off your appearance.” means _________.

A. Smoking and passive smoking can make you look 8 years younger

B. Smoking and passive smoking can make you die 8 years ahead

C. Giving up smoking and avoiding passive smoking can make you live 8 years longer

D. Giving up smoking and avoiding passive smoking can make you look 8 years younger

65. According to the passage, we can know that _________.

A. exercises properly every day helps people retain youth

B. if you want to be 30 years younger you must keep other pressures under control

C. doing whole body check regularly can make people look younger

D. fear and anxiety are a part of our life, which help people realize the importance of keeping youth

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