问题 选择题

下列说法正确的是(  )

①正常雨水的pH为7.0;酸雨的pH小于7.0

②严格执行机动车尾气排放标准有利于防止大气污染

③三大营养素糖类、油脂、蛋白质中,油脂是热能最高的营养素

④用纯碱(Na2CO3)热溶液洗涤餐具上的油污

⑤氯水使红墨水褪色原理和CH2=CH2使Br2的CCl4溶液褪色原理相同

⑥血液、烟水晶和雾都是胶体.

A.①②③

B.②④⑤⑥

C.②③④⑥

D.③④⑤

答案

①正常雨水的PH等于5.6,酸雨的PH小于5.6,故①错误;

②严格执行机动车尾气排放标准可减少大气污染物的排放,有利于防止大气污染,故②正确;

③三大营养素糖类、油脂、蛋白质中,油脂单位质量提供给的热能最高,故③正确;

④纯碱溶液水解显碱性,升温促进水解,油脂在碱性条件下能发生水解,故④正确;

⑤氯水有强氧化性能使红墨水褪色,CH2=CH2与Br2发生加成反应,原理不同,故⑤错误;

⑥血液、烟水晶和雾的分散质微粒直径在1~100nm之间,都是胶体,故⑥正确.

故选C.

单项选择题 A型题
阅读理解

As a boy, Mark Twain caused much trouble for his parents. He used to play practical jokes on all his friends and neighbors. The nature of his jokes often led to violence (暴力). He hated to go to school and he constantly ran away from home. He always went in the direction of the nearby Mississippi. He liked to sit on the bank of the river for hours at a time and just gaze at the mysterious island and the passing boats. He learned many things about the river during those days. He learned all about its history and unusual people. He later made them part of the history of America in the book Tom Sawyer and Huckleberry Finn.

Mark Twain received his genius (天才) from his mother. Obviously he didn’t get it from his father. He once stated that he had never seen a smile on his father’s face. On the other hand, his mother had the ability to say humorous things. The same ability made Mark Twain an extremely humorous public speaker.

小题1:According to the passage, Mark Twain was a _______ boy.

A.shy

B.brave

C.naughty(调皮的)

D.poor小题2:Because of the nature of his jokes when he was a child, Mark Twain would _______.

A.ran away form school

B.cause his parents to quarrel with others

C.get into trouble with his friends and neighbors

D.like to sit on the bank of the Mississippi River小题3:It can be learned form the passage that      ______.

A.Mark Twain’s father was a cruel man

B.Mark Twain never attended school on time

C.Mark Twain often went boating in the nearby river

D.Mark Twain’s mother was something of a humorist小题4:In his book Tom Sawyer and Huckleberry Finn, Mark Twain wrote much about _______.

A.the Mississippi and the people living on it

B.his friends and neighbors

C.his school life

D.his parents小题5:It is inferred that what affected Mark Twain’s character mostly was _______ .

A.his practical jokes

B.his father’s seriousness

C.the history of the Mississippi

D.his mother’s genius for humor