下列反应属于复分解反应的是（ ）
A．Fe2O3+3CO
2Fe+3CO2高温 .
B．2NaOH+H2SO4═Na2SO4+2H2O
C．3NO2+2H2O═2HNO3+NO
D．H2+CuO
Cu+H2O加热 .
A、Fe2O3+3CO
2Fe+3CO2，该反应的生成物中铁属于单质，不是两种化合物相互交换成分生成两种新的化合物的反应，不属于复分解反应，故选项错误．高温 .
B、2NaOH+H2SO4═Na2SO4+2H2O，该反应是两种化合物相互交换成分生成两种新的化合物的反应，属于复分解反应，故选项正确．
C、3NO2+2H2O═2HNO3+NO，该反应不是两种化合物相互交换成分生成两种新的化合物的反应，不属于复分解反应，故选项错误．
D、H2+CuO
Cu+H2O，该反应是一种单质和一种化合物反应生成另一种单质和另一种化合物的反应，属于置换反应，故选项错误．加热 .
故选：B．
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| It is Saturday morning. Sue __1__ breakfast. Sue's mother and father are with her. On Saturday morning Sue __2__ go to school. She helps her mother and father __3__ home. This morning, she says to her mother, "__4__ I help you, Mummy?" "Yes, you can, Sue." her mother says, "You can go to Mr. Hunter's __5__.Our clock is __6__ his shop." "Mr. Hunter mends clock." Sue's father says. "Is he __7__ our clock?" Sue asks. "Yes." her father says, "And this morning it's ready." "Yes, it's ready." her mother says, "__8__ Mr. Hunter's shop, Sue. Take this bag. You can put the clock in it." Sue takes this bag. "Here is eighty pence, Sue." her father says, "Give it to __9__, please." "Yes, Daddy." Sue says. She puts the pence in the bag. "__10__ , Mummy and Daddy." she says. Sue  is happy. She is helping her mother and father. | |||
| ( ) 1. A. is having ( ) 2. A. isn't ( ) 3. A. in ( ) 4. A. do ( ) 5. A. home ( ) 6. A. in ( ) 7. A. mend ( ) 8. A. Go ( ) 9. A. Mrs. Hunter ( ) 10. A. Good morning | B. is hasing B. doesn't B. on B. Do B. shop B. on B. mends B. Go to B. Mr. Hunter B. Good evening | C. has C. don't C. at C. can C. school C. to C. mending C. go C. Miss Hunter C. Good-bye | D. having D. aren't D. to D. Can D. team D. at D. to mend D. go to D. the Hunters D. Good afternoon |