问题 实验题

(1)图甲的螺旋测微器的读数是______mm;图乙的游标卡尺的读数是______mm。

(2)利用油膜法估测油酸分子直径的大小,实验器材有:浓度为0.05%(体积分数)的油酸酒精溶液、最小刻度为0.1ml的量筒、盛有适量清水的4550cm2浅盘、痱子粉、橡皮头滴管、玻璃板、彩笔、坐标纸。

①下面是实验步骤,试填写所缺的步骤C

A.用滴管将浓度为0.05%的油酸酒精溶液一滴一滴地滴入量筒中,记下滴入1ml酒精油酸溶液时的滴数N;

B.将痱子粉均匀地撒在浅盘内水面上,用滴管吸取浓度为0.05%的油酸酒精溶液,从低处向水面中央一滴一滴地滴入,直到油酸薄膜有足够大的面积又不与器壁接触为止,记下滴入的滴数n;

C.

D.将画有油酸薄膜轮廓的玻璃板放在坐标纸上,以坐标纸上边长为1cm的正方形为单位,计算轮廓内正方形的个数,算出油酸薄膜的面积Scm2;②用已给的和测得的物理量表示单个油酸分子的直径为                (单位:cm)

答案

(1)图甲的螺旋测微器的读数是2mm+32.8×0.01mm=2.328mm,

图乙的游标卡尺的读数是11mm+3×0.1=11.3mm

(2)所缺的步骤C:将玻璃放在浅盘上,用彩笔将油酸薄膜的形状画在玻璃板上

单个油酸分子的直径为

故答案为:(1)2.328 ,11.3 (2)将玻璃放在浅盘上,用彩笔将油酸薄膜的形状画在玻璃板上,

阅读理解

                          

The church seems cold this morning, even after all the people, friends and family, fill the benches. I sit here in silence, in shock and denial. This was not supposed to happen. What about our dreams, or our plans? We were going to raise our children, travel the world, and grow old together. I’m only 37, a typical housewife. I don’t know if I can do all this alone—two children, no father. What do I do or say?

The faces of so many people confuse me as they come to pay their last respects. Some have real sorrow; I can see it in their eyes. The others seem to just say, “I told you so.” Those famous last words: I-told-you-so. How I can’t stand them. And the pointing fingers as so-called family and so-called friends pick me out of the crowd for others to see. I want to scream and wake up but I can’t do anything but sit there. How can they be so blind? I fell in love with a man. Love knows no boundaries .

He was a good man, hardworking, caring and kind. He was retired from the Navy and a gentleman. He was sensitive to others’ needs, the kind of man that knew what to do or say, how to humor any situation and calm everyone’s fears. I remember our first child was a big surprise to both of us. I remember when I told him the news. He fell off his chair, saying over and over in disbelief, “But I’m almost sixty.” After a few months he started planning our next and even doing his famous little dance whenever he discussed the idea.

A man, thirty years older than I, lies in a coffin. Flowers, the American flag and his VFW comrades surround him, paying tribute(颂词)to him as the man he really was. And I sit alone here, with our two children, in silence, praying that this cold morning at church is only a nightmare and I will awake to his loving arms again.

49. What can we know from the passage about the writer?

A. She married a man much older than she. 

B. She is going to give birth to their second child.

C. She lost her husband, who was as old as she.

D. She lost her father, whom she loved deeply.

50. From Paragraph Two, we can see ______.

A. the writer didn’t really love the man

B. some of her family members didn’t understand her

C. some of her family members and friends were blind

D. she thought her marriage to the man was a mistake

51. Which of the following can best replace the underlined words “But I’m almost sixty”?

A. I can’t believe it.                  

B. That’s a lot of trouble.

C. That should have happened long ago.    

D. It can’t be my child.

52. Which of the following can’t be used to describe the writer’s feelings for the man?

A. Sad.         B. Loving.        C. Inseparable        D. Complaining.

单项选择题