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问题 选择题

某温度下，H2（g）+CO2（g）

 H2O（g）+CO（g）的平衡常数K=

9
4
．该温度下在甲、乙、丙三个恒容密闭容器中，投入H2（g）和CO2（g），其起始浓度如下表所示．下列判断不正确的是（　　）

起始浓度甲乙丙
c（H2）/mol/L0.0100.0200.020
c（CO2）/mol/L0.0100.0100.020

A．反应开始时，丙中的反应速率最快，甲中的反应速率最慢

B．平衡时，甲中和丙中H2的转化率均是60%

C．平衡时，乙中CO2的转化率小于60%

D．平衡时，丙中c（CO2）是甲中的2倍

答案

A、反应开始时，丙中的物质的浓度最大，反应速率最快，甲中的物质的浓度最小，反应速率最慢，故A正确；

B、甲和丙对比，并相当于是在甲的基础上又加倍增大了物质的加入量，但是对于化学反应前后体积不变的反应，增大压强，化学平衡不移动，物质的转化率不变，根据计算得出甲中H2的转化率均是60%，所以丙中H2的转化率均是60%，故B正确；

C、乙和甲对比，乙相当于在甲的基础上增加了氢气的量，所以乙中二氧化碳的转化率增大，会大于甲中的，即大于60%，故C错误；

D、甲和丙对比，并相当于是在甲的基础上又加倍增大了物质的加入量，但是对于化学反应前后体积不变的反应，增大压强，化学平衡不移动，丙的初始投入量是甲的2倍，所以平衡时，丙中c（CO2）是甲中的2倍，故D正确．

故选C．

选择题

在溶液中能大量共存且溶液无色的一组离子是

A．Mg 2+SO42－ OH－ K+

B．Cu2+ NO3－ Cl－ H+

C．H+ Na+ Cl－ SO42－

D．K+ H+ Cl－ OH－
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单项选择题

Most sore throats are caused by an infection which treatment with antibiotics cannot cure. But with simple remedies the patient normally gets better in 4 or 5 days. Sore throats are common. Most of the time the soreness is worse in the morning and improves as the day progresses.
Like colds, the vast majority of sore throats are caused by viral infections. This means most sore throats will NOT respond to antibiotics. Many people have a mild sore throat at the beginning of every cold. When the nose or sinuses become infected, drainage can run down the back of the throat and irritate it, especially at night. Or, the throat itself can be infected.
With a sore throat, sometimes the tonsils or surrounding parts of the throat are inflamed. Either way, removing the tonsils to try to prevent future sore throats is not recommended for most children.
Tonsillitis, however, usually starts with a sore throat which causes pain on swallowing. With children — and some adults — there may be a fever and the patient is obviously not feeling well. It may be possible to see white spots on the back of the throat. The neck may also swell, both of which are the normal response to infection. Sometimes a sore throat may occur with the common cold, and with influenza there may be dryness of the throat, pain on coughing and loss of voice.
TREATMENT:
Aspirin: To help relieve the pain on swallowing and (if there is one) the fever. Use aspirin tablets dissolved in water so that the patient can gargle before swallowing. Repeat the treatment every 4 hours.
Drink: Encourage the patient to drink plenty.
Food: Food should not be forced on a patient who does not want to eat.
Steam: If there is pain in the throat on coughing, breathing in steam may help. CHILDREN:
Young children, who may not be able to gargle, should be given aspirin dissolved in water every 4 hours in the right dose for their age.
At one year: A single junior aspirin.
At five years: Half an adult aspirin.
At eight years: One whole adult aspirin.
WHEN TO SEE THE DOCTOR.
If the sore throat is still getting worse after 2 days. If the patient complains of earache. If the patient’s fever increases. If the patient or parent is very worried.

According to the passage, it would appear that most sore throats______.

A．(A) require an immediate visit to a doctor

B．(B) respond quickly to treatment with an antibiotic

C．(C) rarely turn out to be serious illnesses

D．(D) result in tonsillitis even when treated
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