问题 填空题

北京奥运会“祥云”火炬燃料是丙烷(C3H8),亚特兰大奥运会火炬燃料是丙烯(C3H6).

(1)丙烷脱氢可得丙烯:已知:

C3H8(g)===CH4(g)+HCCH(g)+H2(g) ΔH1=+156.6 kJ/mol

CH3CHCH2(g)===CH4(g)+HCCH(g) ΔH2=+32.4 kJ/mol

则相同条件下,反应C3H8(g)===CH3CHCH2(g)+H2(g)的ΔH=________kJ/mol.

(2)以丙烷为燃料制作新型燃料电池,电池的正极通入O2和CO2,负极通入丙烷,电解质是熔融碳酸盐.电池反应方程式为________;放电时,CO32-移向电池的________(填“正”或“负”)极.

(3)碳氢化合物完全燃烧生成CO2和H2O.常温常压下,空气中的CO2溶于水,达到平衡时,溶液的pH=5.60,c(H2CO3)=1.5×10-5 mol/L.若忽略水的电离及H2CO3的第二级电离,则H2CO3HCO3+H的平衡常数K1=________.(已知:10-5.60=2.5×10-6)

(4)常温下,0.1 mol/L NaHCO3溶液的pH大于8,则溶液中c(H2CO3)________c(CO32-)(填“>” 、“=”或“<”),原因是____________________(用离子方程式和必要的文字说明).

答案

(1)124.2

(2)C3H8+5O2===3CO2+4H2O ;负

(3) 4.2×10-7 mol/L

(4)> ;HCO3+H2OCO32-+H3O(或HCO3 CO32-+H)、HCO3+H2OH2CO3+OH, HCO3的水解程度大于其电离程度

阅读理解

D

Advertising gives useful information about which products to buy. But modern advertising does more than gives news about products and services. Today’s advertisements, or ads, try to get consumers to buy certain brands(品牌) . Writers of advertising are so skillful they can sometimes persuade a consumer to wear a certain kind of clothing,eat a special kind of cereal, or see a movie. Consumers might never even want a product if they did not see or hear advertisements for it. For example, you probably do not need the newest cereal in the supermarket. There are probably many cereal brands on your kitchen helves. You may not have extra-tasty and has a free prize in the box, you may want it. Advertising must get attention. To be effective, it must be exciting, entertaining, or provide some pleasure. The secret of writing good advertising copy is to offer a good idea as well as a product. The idea is what the ad is really selling. One example is an ad that says eating a certain cereal will make a person do well in sports. That cereal brand may sell better if consumers think it offers strength and energy.

68. What is discussed in this passage?

A. The content of modem advertising.     B. The skills of modern advertising.

C. The results of modem advertising.      D. The writing of modern advertising.

69. According to the passage, a good advertisement should_______.

A. be both persuasive and effective      B. give people useful information

C. show people a product              D. show people a new idea of a product

70. From the passage, we know that ____

A. modem advertising has less effect on customers.

B. once customers see ads about a new cereal, they are sure to buy it.

C. cereal can make people strong.

D. cereal is a kind of food which is popular among people.

单项选择题