试题与答案

下列说法正确的是( ) A.CH3COOH与NaOH在水中都能完全电离 B.Na

题型:多选题

题目:

下列说法正确的是(  )

A.CH3COOH与NaOH在水中都能完全电离

B.NaCl溶液能导电是因为NaCl在水中能电离出自由移动的Na+和Cl-

C.SO3溶于水后,其水溶液能导电,所以SO3是电解质

D.Ba(OH)2是电解质,Ba(OH)2溶于水后能导电

答案:

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题型:解答题

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(1)在A、B两个相同大小的烧杯底部铺上5层纱布,加入适量清水使纱布彻底湿润;

(2)分别在两个烧杯中放入等量刚出芽的小麦种子;

(3)将A烧杯放在温暖光照处;

(4)将B烧杯放在封闭性好且大于烧杯的纸盒中,并将此装置放在温暖处;

(5)每天加适量的水,以保证纱布始终是湿润的.

几天后,他看到的现象记录如下表:

装置现象
A烧杯全部长出绿色的幼叶
B烧杯全部长出黄白色的幼叶
请你根据所给材料回答:

这位同学①探究的问题是:______

②作出的假设是:______

③分析实验现象并得出的结论是:______.

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题型:阅读理解

Thousands of years ago, birthdays were considered special days. On birthdays, the bad spirits were able to harm you and change your life. It was believed that the only way to solve the problem was to have your friends and family around you, so that good wishes and presents would keep the bad spirits away. Also, noisemakers were thought to be used at parties as a way of scaring away the evil spirits.

The custom of lighting candles was created by people believing that the gods lived in the sky. By lighting candles and torches, they were sending a signal or prayer to the gods, so they could be answered. Blowing out the candles and making a wish were thought to be another way of sending a signal or a message.

This is how the way we celebrate our birthdays came about. But different cultures celebrate in different ways.

The birthday story in the Bible(圣经) that we know best is about the birth of the Christ in Bethlehem(地名:伯利恒). For nearly 2000 years since that day, the Christian world has been honoring this birth. The day many Englishmen celebrate is, of course, Christmas. There are other references to birthday parties. King Pharaoh celebrated his birthday by making a feast for his court followers. That was over 4000 years ago. The story of King Herod tells that on his birthday he made a supper for his lords, high captains and other special friends in Galilee (地名:加利利).

小题1: According to the passage, good wishes and presents given by one’s friends and family on his birthday can _____________________.

A.cheer him up

B.prove that he’s a popular person

C.bring him a big fortune

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A.The custom of lighting candles originated with the gods.

B.The gods celebrate their birthdays by lighting candles.

C.People send messages to the gods by lighting or blowing out the candles.

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A.how great the two kings were

B.how different cultures celebrate in different ways

C.the two kings’ excellent cooking skills

D.that their court followers were awarded the special honors小题4: The passage is mainly about __________________.

A.the functions of the noises made on birthdays.

B.how to scare away the bad spirits on birthdays

C.the origin of a famous day Christmas

D.how birthdays came about

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