下已知A~K均为中学化学中的常见物质,它们之间的转化关系如图所示,其中A、D为金

题型:问答题

问题:

下已知A~K均为中学化学中的常见物质,它们之间的转化关系如图所示,其中A、D为金属单质,反应过程中生成的水及其他部分产物已略去.

请回答以下问题:

(1)A和B的反应在工业上也叫做______反应,B物质为______颜色的固体.

(2)F和K的化学式分别为______、______.

(3)写出H在空气中生成I的化学方程式______.

(4)J中的阳离子应该如何检验?______.

考点:无机推断
题型:问答题

为使垫层混凝土表面高程控制在标准以内,首先要控制好垫层侧模板高程的误差值( ),用水准仪测量。

A.≥5mm

B.>5mm

C.≤5mm

D.<5mm

题型:问答题

It was a village in India. The people were poor. However, they were not unhappy. After all, their forefathers had lived in the same way for centuries.

Then one day. Some visitors from another city arrived. They told the villagers there were some people elsewhere who liked to eat frog’ s legs. However, they did not have enough frogs of their own, and so they wanted to buy frogs from other place.

This seemed like money for nothing. There were millions of frogs in the fields around, and they were no use to the villagers. All they had to do was to catch them. Agreement was reached, and the children were sent into the fields to catch frogs. Every week a truck arrived to collect the catch and hand over the money. For the first time, the people were able to dream of a better future. But the dream didn’t last long.

The change was hardly noticed at first, but it seemed as if the crops were not doing so well. More worrying was that the children fell ill more often, and, there seemed to be more insects around lately.

The villagers decided that they couldn’ t just wait to see the crops failing and the children get-ting weak. They would have to use the money earned to buy pesticides (杀虫剂) and medicines. Soon there was no money left.

Then the people realized what was happening. It was the frog. They hadn’ t been useless. They-had been doing an important job—eating insects. Now with so many frogs killed, the insects were increasing more rapidly. They were damaging the crops and spreading diseases.

Now, the people are still poor. But in the evenings they sit in the village square and listen to sounds of insects and frogs. These sounds of the night now have a much deeper meaning.

From paragraph 1, we learn that the villagers().

A. worked very hard for centuries

B. dreamed of having a better life

C. were poor but somewhat content

D. lived a different life from their forefathers

题型:问答题

以下叙述中正确的是( )。

A.局部变量说明为static存储数,其生存期将得到延长

B.全局变量说明为static存储类,其作用域将被扩大

C.任何存储类的变量在未赋初值时,其值都是不确定的

D.形参可以使用的存储类说明符与局部变量完全相同

题型:问答题

请演示 * * 视诊检查的方法。(须口述检查内容)

题型:问答题

利泽花园住宅小区由瑞辰物业管理公司进行物业管理。在物业服务合同中约定采用包干制计算物业服务费,物业费标准为每平方米2.8元。但由于近期物价上涨,导致用工成本提高,使得瑞辰物业公司产生亏损约10万元。请回答下列问题。

瑞辰物业公司的亏损应按( )处理。

A.由瑞辰物业公司自行承担

B.由利泽花园住宅小区的业主共同承担

C.由瑞辰物业公司和利泽花园小区的业主委员会协商解决

D.由瑞辰物业公司承担,但是利泽花园住宅小区的业主应对物业公司给予一定比例的补偿

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