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已知在1×105Pa，298K条件下，2mol氢气燃烧生成液态水放出528kJ热量，下列表示氢气燃烧的热化学方程式的是[ ]

A．H2O(g) = H2(g)＋1/2O2(g) △H＝+264kJ·mol-1

B．2H2(g)+ O2(g)=2H2O(g) △H＝－528kJ·mol-1

C．H2(g)＋1/2O2(g)=H2O(l) △H＝+264 kJ·mol-1

D．H2(g)+ 1/2O2(g)= H2O(l) △H＝－264kJ·mol-1

答案

答案：D

填空题

Today’’s lecture we’’ll center on the prehistoric people of Nevada Desert. Now most of these prehistoric desert people (36)______the countryside throughout the year. You might think that they’’re wandering aimlessly. Far from it, they actually followed the (37)______of carefully planned moves. Where they moved depended on where food was (38)______. Places where plants were ripening or fish were (39)______. Now often when these people moved, they carried all their (40)______on their backs. But if the journey was long, extra food and tools were sometimes stored in caves or (41)______rocks. One of these caves is now an exciting (42)______ site. Beyond its small opening is a huge underground (43)______. Even though the cave is very large. It was certainly too dark and dusty for the travelers to (44)____________. But it was a great place to (45)____________. And tremendous amounts of food supplies and artifacts have been found there.The food includes dried fish, seeds and nuts. The artifacts include stone spear points and (46)____________. The spear points are actually rather small. Here is a picture of some that were found. You can see their size in relation to the hands holding them.
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多项选择题

下述因素中，提示类风湿关节炎预后较差的是（）

A.2年内发生关节骨侵蚀

B.HLA-DR阳性

C.抗核抗体阳性

D.类风湿因子持续高滴度阳性

E.多发类风湿结节
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