下列有关热化学方程式的评价合理的是( ) 实验事实热化学方程式评价A已知H+(a

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问题:

下列有关热化学方程式的评价合理的是(      )

 实验事实热化学方程式评价
A已知H+(aq)+OH-(aq)=H2O(l)

△H=-57.3 kJ·mol-1,将稀硫酸与稀氢氧化钡溶液混合

H2SO4(aq)+Ba(OH)2(aq)

=BaSO4(s)+ 2H2O(l)

△H=-114.6 kJ·mol-1

正确
B醋酸与稀氢氧化钠溶液混合CH3COOH(aq)+NaOH(aq)

=CH3COONa(aq)+H2O(l)

△H=-57.3kJ·mol-1

不正确;因为醋酸状态为“aq”,而不是“l”。
C160 g SO3气体与适量水恰好完全反应生成H2SO4,放出热量260.6 kJSO3(g)+H2O(l)=H2SO4(aq) △H=-130.3 kJ·mol-1不正确;因为反应热为△H=-260.6kJ·mol-1
D已知25℃、101 kPa下,120g石墨完全燃烧放出热量3935.1 kJC(s)+O2(g)=CO2(g)

△H=-393.51 kJ·mol-1

不正确;同素异形体要注名称:C(石墨)
 

考点:能量的相互转化
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下列心脏杂音的产生机制,正确的是

A.只要血流速度加快,即使没有血管狭窄也可产生杂音

B.随着血液粘稠度的增加,不仅产生杂音而且强度增大

C.没有瓣膜病变者,当血流速度减慢时也可产生杂音

D.瓣膜口狭窄越严重,产生的杂音越强

E.动脉壁局限性扩张时,血流速度减慢而不产生杂音

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一个水池有进水管甲和出水管乙,单独开放甲管10分钟可以注满水池,单独开放乙管15分钟可以把满水池的水放尽.一次,由于工作人员的疏忽,在打开甲管后若干分钟才匆忙关闭乙管,又过了相同的时间才注满全池,造成了浪费.问甲管一共注水多少时间?

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阅读理解。

     Mariah Evans at the University of Nevada, Reno, led a 20-year study which asked adults in 27 countries

to tell the number of books that were in their home while they were growing up. Their answers showed that

children raised around books spend more years in school, even if their parents are poor and illiterate (没文化

的).

     Mariah Evans said, "What we found was that there is a very big effect of growing up in a bookish home

on children's success in school. Children who grow up in homes where there are more books go further in

education. And additional (额外的) books are especially important for children who come from families

where the parents aren't terribly highly educated. The books can be stories, sports, travels and anything. But

there, we're seeing that the books that have the most effect are history and science."

     "It says that there really is a contribution that parents can make to their children's education. And it doesn't

mean that you have to turn into somebody like me whose walls are lined with books. "But it really does mean

that if you spend a few minutes most days a week reading to your children, and if they see you reading from

time to time, and if you talk about books with them from time to time, and when somebody asks a question,

say 'let's look it up' instead of discussing it as a matter of opinion-that all those things can actually make quite

a great difference to children in their education."

1. It can be inferred from the passage that _____. [ ]

A. it is more difficult for children raised around books to finish school

B. highly educated parents prevent a child going further in education

C. more books are needed by children from poor and illiterate families

D. children with poor parents don't spend as many years in school

2. According to the author, the books most important for the children are _____. [ ]

A. history and science

B. sports and education

C. stories and travels

D. all kinds of subjects

3. Wise parents can make quite a great difference to children in their education by _____. [ ]

A. turning themselves into somebody whose walls are lined with books

B. spending some minutes most days a week playing with their children

C. discussing them rather than looking up questions with their children

D. talking about books with their children from time to time

4. This passage mainly talks about _____. [ ]

A. the effect of bookish home on children

B. the importance of parents

C. the necessity of reading more books

D. the interest of children in books

题型:选择题

患者,女性,55岁,无外伤史,诉腰痛。该患者诊断最先考虑为()

A.骨关节炎

B.椎间盘突出症

C.骨质疏松症

D.肾结石

E.以上都有可能

题型:选择题

漂移电流是()电流,它由()载流子形成,其大小与()有关,而与外加电压()。

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