hòa tan hoàn toàn 2,7g al vào dung dịch hcl

trong các oxit sau :k2o, cuo ,cao ,so2, feo, p2o5.

tính phaần trăm về khối lượng của nguyên tố oxi trong hợp chất P2O5

Read the following passage and do the tasks below. 

       Almost a hundred thousand people were killed and half a million homes destroyed as a result of an earthquake in Tokyo in 1923. The earthquake began a minute before noon when the inhabitants of Tokyo were cooking their midday meals. Thousands of stoves were overturned as soon as the earth began to shake.

       As a result, small fires broke out everywhere and quickly spread. The fire engines were prevented from going to help because many of the roads had cracked open. It was impossible to use fire fighting equipment as most of the water pipes had burst. Consequently, over ninety percent of the damage was caused by fire rather than by the collapse of the buildings. Most of those who died were not killed in the earthquake itself but in the fires, which followed. If the earthquake had occurred at night while people were sleeping, far fewer would have died.

A. Answer the following questions.

1. How many people were killed after the earthquake?

2. Why were the engines prevented from going to help?

3. Was it possible to use fighting equipment?

B. Choose the correct answer.

4. When did the earthquake start?

A. in the afternoon                   B. before noon                   C. at night                                            D. after midday meals

5. What was the main cause of the damage and death of most people? 

A. The roads                              B. The collapse of the building     C. The water pipes              D. The fire                              

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