问题 填空题

用>、<、=、≥、≤填空.

(1)沸点:液氮______液氧

(2)阴离子中的电子数______质子数

(3)10gA物质和5gB物质混合,经过化合反应生成C,生成C物质的质量______15g

(4)某露置在空气中发生变质的烧碱溶液与10%盐酸完全反应所消耗盐酸的体积______原来没有发生变质的该烧碱溶液完全中和所需10%盐酸的体积.

答案

(1)沸点:液氮<液氧;

(2)根据“阴离子中,核电荷数=质子数<核外电子数”,则阴离子中的电子数>质子数;

(3)10gA物质和5gB物质混合,经过化合反应生成C,反应物分:完全反应或某一种物质剩余,则生成C物质的质量≤15克;

(4)氢氧化钠溶液变质,但根据质量守恒定律的元素守恒,钠元素的质量不变,上述反应实质为“氯离子与钠离子的结合”,则某露置在空气中发生变质的烧碱溶液与10%盐酸完全反应所消耗盐酸的体积=原来没有发生变质的该烧碱溶液完全中和所需10%盐酸的体积.

故答为:(1)<;(2)>;(3)≤;(4)=

阅读理解

阅读理解。

     A Sally and Tom are classmates. Here are their plans for next weekend.

     Sally's plan

Saturday 

9∶00 a.m.~10∶00 a.m.     take part in the English corner

4∶00 p.m.~5∶00 p.m. have an art lesson

8∶00 p.m.~10∶00 p.m. be at Alice's birthday party

Sunday 

8∶00 a.m.~10∶30 a.m. do some reading at home

3∶30 p.m.~5∶00 p.m. draw pictures in the park

7∶00 p.m.~9∶30 p.m. do my homework

                                           Tom's play

Saturday 

8∶00 a.m.~10∶00 a.m.     do my homework at home

4∶30 p.m.~5∶45 p.m. play basketball

8∶00 p.m.~10∶00 p.m. be at Alice's birthday party

Sunday 

8∶20 a.m.~11∶00 a.m. roller skate

4∶05 p.m.~5∶30 p.m. climb the hill

7∶30 p.m.~9∶30 p.m. watch TV

1. Sally will stay in the park for ________ on Sunday afternoon.

A. one hour

B. two hours

C. one and a half hours

D. two and a half hours

2. Sally will be free at ________.

A. 9∶30 a.m. on Saturday

B. 4∶25 p.m. on Saturday

C. 10∶50 a.m. on Sunday

D. 4∶30 p.m. on Sunday

3. Tom will be ________ at 9∶25 on Saturday morning.

A. at home

B. on the playground

C. on the hill

D. in the park

4. Both Sally and Tom plan to ________ next Saturday evening.

A. do some reading

B. do their homework

C. go to the English corner

D. go to Alice's birthday party

5. According to Tom's plan, we know he prefers ________.

A. drawing pictures

B. doing exercise

C. watching TV

D. reading books

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