问题 问答题

A、B、C、D四种有机物分子中碳原子数相同,A在标况下的密度为1.161g•L-1;B或D跟溴化氢反应都生成C;D在浓硫酸存在下发生消去反应生成B.

(1)A、B、C、D的结构简式分别是______、______、______、______.

(2)写出下列反应的化学方程式及部分反应类型

B→C______.属于______反应.

D→C______.属于______反应.

D→B______.

答案

(1)A在标况下的密度为1.161g•L-1,则相对分子质量为1.161×22.4=26,应为CH≡CH,则A、B、C、D四种有机物分子中碳原子数都为2,D在浓硫酸存在下发生消去反应生成B,可知D为CH3CH2OH,B为CH2=CH2,则C为CH3CH2Br,

故答案为:CH≡CH;CH2=CH2;CH3CH2Br;CH3CH2OH;

(2)CH2=CH2和HBr发生加成反应,反应的方程式为CH2=CH2+HBr→CH3CH2Br,

CH3CH2OH和HBr可发生取代反应生成CH3CH2Br,反应的方程式为C2H5OH+HBr

H2SO4
C2H5Br+H2O,

CH3CH2OH在浓硫酸存在下发生消去反应生成CH2=CH2,反应的方程式为C2H5OH+HBr

H2SO4
C2H5Br+H2O,

故答案为:CH2=CH2+HBr→CH3CH2Br;加成;C2H5OH+HBr

H2SO4
C2H5Br+H2O;取代;C2H5OH+HBr
H2SO4
C2H5Br+H2O.

阅读理解

( D )

Your body works 24 hours a day. It’s always building and repairing, feeding and cleansing itself. Its goal is to be ready for your every movement, breath, and thought. The quality of your life depends on how well your body works. And how well your body works depends on how much energy it gets. Energy comes from the food you eat. Food contains nutrients that your body needs for growth and energy.

By eating a balanced diet, your body gets the six important nutrients it needs. Minerals(矿物质) are nutrients that build bones and teeth. Minerals also form red blood cells and other substances. Water aids digestion and waste removal. Carbohydrates(碳水化合物) give your body its main source of energy. Two carbohydrates are sugars from foods such as fruits and vegetables and starches found in rice, potatoes, and bread. Fats help build cell membranes(膜). Proteins repair and grow body tissues(组织). Finally, vitamins help your body use carbohydrates, fats, and proteins.

The United States Department of Agriculture(USDA) has created a nutritional food pyramid(金字塔). It shows the daily number of servings you should eat from five food groups. The food pyramid has four levels. The base of the pyramid is the largest level. It contains the bread, cereal, rice, and pasta group from which you need six to eleven servings. The next level has two food groups: vegetables and fruits. The USDA recommends three to five servings of vegetables and two to four servings of fruit. The third level also has two groups: the milk, yogurt, and cheese group and the meat, poultry, fish, dry beans, eggs, and nuts group. You need two to three servings from each of these groups. The top of the pyramid is the smallest level. It contains fats, oils, and sweets. These foods have few nutrients, so eat them sparingly(有节制地).

小题1:What is the main idea for this passage_________?

A.Eating a balanced diet gives your body the energy it needs.

B.The top of the pyramid is the smallest level.    

C.Meat, poultry, fish, dry beans, eggs, and nuts are on the third level.

D.We should have a nutrition food pyramid.小题2:The first paragraph suggests that __________?

A. food is something that cleanses your body.

B.food can improve the quality of your life.

C.food should be eaten at night as well as during the day.

D.food will make it easier for you to exercise.小题3:By eating a balanced diet, your body gets the      important nutrients it needs.

A.four

B.five

C.six

D.seven小题4:A balanced diet________.

A.is made up of foods from five food groups.

B.includes many foods containing fat.

C.includes six to eleven servings of fruit.

D.can be got by taking vitamins.小题5:To help the reader understand the six nutrients needed by the body, the author________.

A.describes the five basic food groups.

B.explains what a balanced diet is.

C.writes the details of each nutrient.

D.tells the number of daily servings needed from each food group.

填空题