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问题 填空题

写出下列化学方程式

（1）铁和硫酸铜溶液反应______

（2）硫酸和氯化钡溶液反应______

（3）硫酸铜溶液和氢氧化钡溶液反应______

（4）碳酸钾和稀硫酸溶液反应______

（5）盐酸和硝酸银溶液反应______．

答案

（1）铁和硫酸铜溶液反应生成铜和硫酸亚铁，化学方程式为：Fe+CuSO4═Cu+FeSO4

（2）硫酸和氯化钡溶液反应生成硫酸钡沉淀和氯化氢，该反应的化学方程式为：H2SO4+BaCl2=BaSO4↓+2HCl

（3）硫酸铜溶液和氢氧化钡溶液反应生成氢氧化铜沉淀和硫酸钡沉淀，该反应的化学方程式为：Ba（OH）2+CuSO4═Cu（OH）2↓+BaSO4↓．

（4）碳酸钾和稀硫酸溶液反应生成硫酸钾、水和二氧化碳，该反应的化学方程式为：K2CO3+H2SO4=K2SO4+H2O+CO2↑．

（5）盐酸和硝酸银溶液反应生成氯化银沉淀和硝酸，该反应的化学方程式为：HCl+AgNO3═AgCl↓+HNO3．

故答案为：

（1）Fe+CuSO4═Cu+FeSO4；

（2）H2SO4+BaCl2=BaSO4↓+2HCl；

（3）Ba（OH）2+CuSO4═Cu（OH）2↓+BaSO4↓．

（4）K2CO3+H2SO4=K2SO4+H2O+CO2↑

（5）HCl+AgNO3═AgCl↓+HNO3

填空题

慢性肺源性心脏病的主要心电图改变有__________、__________、__________和__________。
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单项选择题

Scientists around the world are racing to learn how to rapidly diagnose, treat and stop the spread of a new, deadly disease. SARS — Severe Acute Respiratory Syndrome — was (1) for the first time in February 2003 in Hanoi, (2) since then has infected more than 1,600 people in 15 countries, killing 63. At this (3) , there are more questions than answers surrounding the disease.

Symptoms start (4) a fever over 100.4 degrees F, chills, headache or body (5) . Within a week, the patient has a dry cough, which might (6) to shortness of breath. In 10% to 200% of cases, patients require (7) ventilation to breathe. About 3.5% die from the disease. Symptoms (8) begin in two to seven days, but some reports suggest it (9) take as long as 10 days. Scientists are close to (10) a lab test to diagnose SARS. In the meantime, it is diagnosed by its symptoms. There is no evidence (11) antibiotics or anti-viral medicines help, (12) doctors can offer only supportive care. Patients with SARS are kept in isolation to reduce the risk of (13) . Scientists aren’t sure yet, but some researchers think it’s a (14) discovered coronavirus, the family of viruses that cause some common colds.

Most cases appear to have been passed (15) droplets expelled when infected patients cough or sneeze. Family members of infected people and medical workers who care for them have been most likely to (16) the illness. But recent developments in Hong Kong suggest that the (17) might spread through air, or that the virus might (18) for two to three hours on doorknobs or other (19) Health experts say it is (20) , though, that sharing an elevator briefly with an infected person would be enough to pass the virus.

5（）

A.hurt

B.sore

C.aches

D.feelings
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