亚氯酸钠(NaClO2)是一种强氧化性漂白剂,广泛用于纺织、印染和食品工业。它在

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亚氯酸钠(NaClO2)是一种强氧化性漂白剂,广泛用于纺织、印染和食品工业。它在碱性环境中稳定存在。某同学查阅资料后设计生产NaClO2的主要流程如下。

(1)双氧水的结构式为:           ;Ⅰ中发生反应的还原剂是     (填化学式)。

(2)Ⅱ中反应的离子方程式是                              

(3)A的化学式是        ,装置Ⅲ中A在        极区产生。

(4)ClO2是一种高效水处理剂,可用亚氯酸钠和稀盐酸为原料制备。

①写出该反应的化学方程式       

②研究表明:若反应开始时盐酸浓度较大,则气体产物中有Cl2,用离子方程式解释产生Cl2的原因                               

(5)NaClO2变质可分解为NaClO3和NaCl。取等质量变质前后的NaClO2试样均配成溶液,分别与足量FeSO4溶液反应时,消耗Fe2+的物质的量       (填相同、不相同或无法判断)

考点:气体的收集、净化、干燥氯气的制取其他物质的制备(硫酸铜晶体、铁红等)乙烯的制取
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已知直角三角形的两条直角边分别为5和5,那么斜边长应为(  )(结果用最简二次根式)
A.5
2
B.
50
C.2
5
D.以上都不对
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经营租赁进口货物一般不复运出境。

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施工工艺卡反映的是( )。

A.有针对性的具体项目的施工方法

B.一般的施工操作要求

C.特定的工艺操作标准

D.施工程度较科学,并且劳动力、工具设备配备较为合理的条件下的规范化的标准施工操作方法

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In the United States, older people rarely live with their adult children. But in many other cultures children are expected to care (1) their aged parents. In some parts of Italy, the percentage of adult children who (2) with their parents (3) 65 to 70 percent. In Thailand, too, children are expected to take care of their elderly parents; few Thai elderly live (4) . What explains these differences in living arrangements (5) cultures Modernization theory (6) the extended family household to low levels of economic development. In traditional societies, the elderly live with their children in large extended family units for economic reasons. But with modernization, children move to urban areas, leaving old people (7) in (8) rural areas. Yet modernization theory cannot explain why extended family households were never common in the United States or England, or why families in Italy, which is fully modernized, (9) a p tradition of intergenerational living. Clearly, economic development alone cannot explain (10) living arrangements. Another theory associated intergenerational living arrangements with inheritance patterns. In some cultures, the stem family pattern of inheritance (11) . (12) this system, parents live with a married child, usually the oldest son, who then (13) their property when they die. The stem family system was once common in Japan, but changes in inheritance laws, (14) broader social changes brought (15) by industrialization and urbanization, have (16) the (17) .In 1960 about 80 percent of Japanese over 65 lived with their children; by 1990 only 60 percent did-a figure that is still high (18) U.S. standards, but which has been (19) steadily. In Korea, too, traditional living arrangements are (20) : the percentage of aged Koreans who live with a son declined from 77 percent in 1984 to 50 percent just 10 years later. Although most elderly Koreans still expect to live with a son, their adult children do not expect to live with their children when they grow old.

(20)是()

A.receding

B.removing

C.invading

D.eroding

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在一级废水处理系统中,最主要的处理工艺是( )。

A.沉淀

B.离心

C.絮凝

D.中和

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