题目

（1）今有2H2+O22H2O反应，构成燃料电池，则电极反应式为：负极____________________、正极__________________。 （2）如把H2改为甲烷，KOH做导电物质，则负极电极反应式为_____________   答案：（1）负极：2H2+4OH－－4e－＝4H2O  正极：O2+2H2O+4e－＝4OH－ （2） 负极：CH4+10OH－－８e－＝CO32-+７H2O A businessman walks into a bank in San Francisco and asks for the loan officer. He says he is going to Europe on business for two weeks and needs to borrow $5,000．The bank officer says the bank will need some kind of security for such a loan. So the businessman hands over the keys to a Rolls Royce parked on the street in front of the bank. Everything checks out, and the bank agrees to accept the car as collateral for the loan. An employee drives the Rolls into the bank’s underground garage and parks it there.Two weeks later, the businessman returns, and repays the $5,000 and the interest, which comes to $15.41.The loan officer says, “We are very happy to have had your business, and this transaction has worked out very nicely, but we are a little puzzled. While you were away, we checked you out and found that you are a multimillionaire. What puzzles us is that why would you bother to borrow $5,000?”Laughing, the businessman replies, “Where else in San Francisco can I park my car for two weeks for $15?”1.The businessman walks into the bank with the true purpose of _________.A. borrowing $5,000 B. meeting the loan officerC. finding a place to park his car D. showing how rich he is2.The loan officer is puzzled because _________.A. he never thought he could meet a multimillionaire in his bankB. he thinks the businessman is crazy to leave his car in the bankC. he never thought the businessman could drive a Rolls RoyceD. he thinks $5,000 is so small a sum of money to the businessman3.The underlined word “collateral” in Paragraph 1 most probably means “_________”.A. security B. paymentC. reward D. deal4.Which of the following words can best describe the businessman according to the story?A. Honest. B. Clever.C. Rich. D. Kind.