问题 填空题

(4分)下图为氯化钠和碳酸钠的溶解度曲线,请回答:

(1)20℃时向lOOg水中加入30g氯化钠,所得溶液为     溶液(填“饱和”或“不饱和”);将上述溶液蒸发掉50g水后恢复到20℃,析出的固体质量是______g。

(2)向A、B两个烧杯中各加入100g水,分别配成60℃的氯化钠和碳酸钠饱和溶液,再冷却到10℃,________(填“A”或“B”)烧杯中析出固体较多。

答案

(1)不饱和;12; (2)B;

(1)20℃时,氯化钠的溶解度是36g,所以lOOg水中加入30g氯化钠,所得溶液为不饱和溶液。20℃时,50g水最多能溶解18g氯化钠,所以洗出12g氯化钠。由于氯化钠的溶解度收温度影响小,而碳酸钠的溶解度收温度影响大,冷却后析出固体较多的是碳酸钠,选B。

阅读理解

Pure Brightness Festival, also known as Tomb-sweeping Day in China, falls on the 4th or 5th of April each year. It was started in the Han Dynasty. On this day, whole families, young and old, with flowers visit the graves of their ancestors to pay their respects. Following the custom, tomb sweepers clean and tidy the graves, decorate them with flowers. They burn paper money made for the dead, set off firecrackers and bow before their ancestors’ tombstones. On this day, they don’t cook. Only cold food is served.

However, tomb sweeping is not the only activity during Pure Brightness Festival. This day is also a time for people to enjoy themselves. Other activities include spring outing, flying kites, planting trees, tasting tea and so on. In April, everything in nature takes on a new look. Trees turn green, flowers come out and the sun shines brightly. So it is a good time to be out to appreciate the beauty of nature. People fly kites not only in the daytime but at night. In the dark, some people fly kites with lanterns, which are called “God’s lanterns”. They plant trees because young trees which are planted during this period are easy to grow up. And they enjoy tea because the tea produced around the festival is said to have good quality.

小题1:The word “tomb” probably means the same as the word “______” in the passage.

A.grave

B.tombstone

C.ancestor

D.custom小题2:From the passage we can learn that Pure Brightness Festival in 2014 will be on ______.

A.April 4

B.April 5

C.either April 4 or April 5

D.neither April 4 nor April 5小题3:According to the passage, Pure Brightness Festival is ______.

A.a day full of sadness

B.Tree Planting Day

C.a combination of sadness and happiness

D.a time for people to have fun小题4:_____ activities are talked about in the passage above.

A.Two

B.Three

C.Four

D.Five小题5:Which of the following do you think is the best title for the passage ?

A.A Special Day

B.Pure Brightness Festival in China

C.What the Chinese Do on Tomb-sweeping Day

D.A Chinese Traditional Custom

判断题