部分中学化学常见元素原子结构及性质如表所示 (1)如果A与冷的浓硝酸作用发生钝化

题型:推断题

问题:

部分中学化学常见元素原子结构及性质如表所示

(1)如果A与冷的浓硝酸作用发生钝化,工业上冶炼A单质的化学方程式为__________________。

(2)A的氯化物的浓溶液分别滴入冷水、热水中,得到黄色和红褐色液体,区别两种液体的方法是________________________。

(3)B与C简单离子的半径大小为___________(用离子符号表示)

(4)F与E可以按原子个数比2:1、1:1形成两种化合物X、Y,区别X、Y这两种物质的实验方法为:____________________________,F与C组成的两种化合物M、N,所含电子数分别与X、Y相等,请写出M的电子式___________,N的化学式_____________。

考点:元素的推断氧化铁元素周期律电子式的书写物质的鉴别
题型:推断题

游标卡尺读数是             cm,螺旋测微器的计数是             mm。

   

题型:推断题

根据世界卫生组织的规定,老年前期是指()

A.44岁以下

B.45~59岁

C.60~74岁

D.75岁以上

E.90岁以上

题型:推断题

阅读理解。

     Good health is the most valuable thing a person can have, but one cannot take good health for

granted. It is important to remember that the body needs proper care in order to be healthy. There

are three things that a person can do to help stay in good shape: eat right food ,get enough sleep,

and exercise regularly.

     Proper nutrition (营养) is important for good health. Your body cannot work well unless it

receives the proper kind of “fuel”(燃料).Don't eat too much food with lots of sugar and fat. Eat

plenty of foods high in protein (蛋白质) ,like meat, fish, eggs and nuts. Vegetables and fruits are

very important because they provide necessary vitamins (维他命) and minerals. However, don't

over eat. It is not helpful to be overweight.

     Getting the proper amount of sleep is also important. If you don't get enough sleep, you feel

tired and easily get angry. You have no energy. Over a long period of time a little a amount of

sleep may even result in a change of personality (人的个性).Be sure to allow yourself from seven

to nine hours of sleep each night. If you do, your body will feel strong and refreshed, and your

mind will be sharp.

     Finally, get plenty of exercise. Exercise firms the body, strengthens the muscles,and prevents

you from gaining weight. It also improves your heart and lungs. If you follow a regular exercise

program, you will probably increase your life-span (寿命).Any kind of exercise is good. Most s

ports are excellent for keeping the body in good shapes: basketball, swimming, bicycling, running

and so on are good examples. Sports are not only good for your body, but they are enjoyable and

interesting, too.

     If everybody, were to eat the right foods, get plenty of sleep and exercise regularly, the world

would be a happier and healthier place. We would all live to be much older and wiser.

1. According to the passage,_________.

A .we should eat right food, get enough sleep, and exercise regularly.

B. if we were healthy, we could spend our days in doing things with less sleep

C. one can eat a lot to stay in good shape

D. one needn't take any exercise if he is healthy

2.In order to keep good health, ___________ .

A.we should eat a lot of sweets              

B.one needs a large amount of fat

C.people should eat according to the foods nutrition    

D. we must try to sleep now and then

3. Eating more and sleeping less________.

A. can keep healthy                

B. is no good for you

C. gets you more energy          

D. will keep your personality

4.The writer explains ________in this passage.

A. how to eat                         B. the importance of doing exercise

C. how to keep healthy             D. what to eat

5.The title of the article should be___________ .

A. Eating and Exercising          

B. How Vitamins Work in Man's Body

C. Staying Healthy                  

D. Sleeping Well

题型:推断题

(10分)如图所示,绷紧的传送带与水平面的夹角θ=300,皮带在电动机的带动下,始终保持V="2" m/s的速率运行.现把一质量m="10" kg的工件(可看做质点)轻轻放在皮带的底端,经时间t="1.9" s,工件被传送到h="1.5" m的高处,取g="10" m/s2.求:

(1)工件与皮带间的动摩擦因数;

(2)电动机由于传送工件多消耗的电能

题型:推断题

对某一会计事项有多种不同方法可供选择时,应尽可能选择可以避免虚增企业利润的会计处理方法,这样做所遵循的原则是( )。

A.重要性原则
B.谨慎性原则
C.权责发生制原则
D.配比原则

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