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问题 选择题

下列有关实验的说法错误的是（　　）

A．浓硫酸溅到皮肤上，应先用水冲洗，再涂上小苏打稀溶液

B．称量物质时，先取用较大砝码再依次取用较小砝码

C．浓HNO3和浓H2SO4的混合物是实验室常用试剂，配制该混合物时，应将浓HNO3缓缓加入到浓H2SO4中，并不断搅拌

D．实验室需要12g食盐（5g以下用游码），如采取左码右物称量，则称取食盐的实际质量比要求的要小

答案

A、浓硫酸不慎沾到皮肤上，应立即用大量的水冲洗，再涂上3%--5%的碳酸氢钠溶液，故A正确；

B、在使用天平时要严格按照规定操作，否则会产生误差．左物右码，在加砝码时先加大的，再加小的，最后移动游码，故B正确；

C、由于浓H2SO4的密度比浓HNO3的密度大，应该将浓H2SO4缓缓加入到浓HNO3中，故C错误；

D、由左盘的质量=右盘的质量+游码的质量可知：砝码质量=物体质量+游码的质量，所以物体质量=砝码质量-游码质量，故称取食盐的实际质量比要求的要小，故D正确．

故选C．

完形填空
Six-year-old Brandon decided to make pancakes for his parents. He should first take the flour(面粉), so he   46  the cupboard and pulled out the heavy flour bag. He put some flour   47  the bowl with his hands, mixed in a cup of milk and added some sugar.
Soon Brandon was  48  flour and getting frustrated, He wanted this to be   49  for Mum and Dad, but it was getting very bad. He didn't know what to do   50 .
Suddenly he saw his cat near the bowl and went to push it away, but he   51  the egg box to the floor. He tried to   52  but slipped(滑倒) on the eggs, getting his clothes   53 . Just then, he saw his dad standing at the door.
Brandon's eyes were full of tears. He was   54  his dad would beat him, but his father didn't.   55 , he picked up his crying son and kissed him.
That's what we sometimes face in   56 . We try to do something good, but it turns into a mess. Sometimes we just   57  there in tears because we can't think of anything else to do. Hopefully, that's   58  someone close to us picks us up, loves us and forgives us. But we can't    59  trying to "make pancakes" for "Dad" or for others. Sooner or later we'll get it   60 , and then they'll be glad we tried.
小题1:
A．turned onB．turned offC．closedD．opened
小题2:
A．aboveB．atC．intoD．under
小题3:
A．full ofB．covered withC．good atD．used for
小题4:
A．something goodB．anything bad
C．everything badD．nothing good
小题5:
A．certainlyB．alreadyC．recentlyD．next
小题6:
A．fellB．brokeC．knockedD．sent
小题7:
A．clean upB．get upC．grow upD．take up
小题8:
A．cleanB．bigC．cheapD．dirty
小题9:
A．sureB．confidentC．happyD．excited
小题10:
A．ThereforeB．BesidesC．InsteadD．But
小题11:
A．lifeB．timeC．useD．space
小题12:
A．layB．landC．studyD．stand
小题13:
A．whetherB．whenC．whereD．how
小题14:
A．stopB．keepC．mindD．finish
小题15:
A．terribleB．difficultC．rightD．necessary
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单项选择题

在美国，有严格的枪支控制的法律的州中，1986年平均犯罪率是100 000人中有645起犯罪——比11个从来没有通过严格的枪支控制法律的州的平均犯罪率高出约50%。所以，减少暴力犯罪的一个方法是废止严格的枪支控制法律。 以下哪项如果为真，最能削弱上述论证

A．有严格的枪支控制法律的州中，每年的暴力犯罪自从通过这些法律以来已经降低了。

B．在有严格的枪支控制法律的州中，违反了这些法律的人很少不受控告。

C．在没有严格的枪支控制法律的州中，许多人从来没有受过使用枪支的正规训练。

D．有严格的枪支控制法律的州中的非暴力犯罪率比没有严格的枪支控制法律的州低。

E．在没有严格的枪支控制法律的州中居住的个人不到一半拥有一支枪。
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