问题 实验题

某教师在课堂上用下图所示的装置来验证浓硫酸与铜是否发生反应并探讨反应所产生气体的性质。请回答下列问题:

(1)通过试管乙中发生的            现象说明了铜和浓硫酸发生了化学反应,并且该现象还能说明产生的气体具有     性。

(2)若要收集试管甲中生成的气体,可以采用       收集方法。

①排水取气法    ②向上排空气取气法    ③向下排空气取气法

(3)写出试管甲中所发生反应的化学反应方程式                               

(4)试管乙口部浸有碱液的棉花的作用是                                     

此防范措施也说明产生的气体是           气体(填“酸性”、“中性”或“碱性”)。

答案

(1)品红溶液   漂白性     (2)②

(3)Cu+2H2SO4(浓) CuSO4+SO2↑+2H2O

(4)吸收产生的SO2气体     防止污染环境   酸性

(1)SO2检验漂白性,能使品红溶液褪色,据此可以说明铜和浓硫酸发生了化学反应。

(2)SO2易溶于水,但密度大于空气的,所以可用向上排空气法收集,答案选②。

(3)方程式为Cu+2H2SO4(浓) CuSO4+SO2↑+2H2O。

(4)SO2是一种大气污染物,同时也是一种酸性气体,可用碱液吸收。

单项选择题

The Bush administration is about to propose far-reaching new rules that would give people with disabilities greater access to tens of thousands of courtrooms, swimming pools, golf courses, stadiums, theaters, hotels and retail stores. The proposal would substantially update and rewrite federal standards for enforcement of the Americans With Disabilities Act, a landmark civil rights law passed with p bipartisan support in 1990. The new rules would set more stringent requirements in many areas and address some issues for the first time, in an effort to meet the needs of an aging population and growing numbers of disabled war veterans.

More than seven million businesses and all state and local government agencies would be affected. The proposal includes some exemptions for parts of existing buildings, but any new construction or renovations would have to comply. The new standards would affect everything from the location of light switches to the height of retail service counters, to the use of monkeys as "service animals" for people with disabilities, which would be forbidden’.

The White House approved the proposal in May after a five-month review. It is scheduled to be published in the Federal Register on Tuesday, with 60 days for public comment. After considering those comments, the government would issue final rules with the force of law. Already, the proposal is stirring concern. The United States Chamber of Commerce says it would be onerous and costly, while advocates for disabled Americans say it does not go far enough.

Since the disability law was signed by the first President Bush, advances in technology have made services more available to people with disabilities. But Justice Department officials said they were still receiving large numbers of complaints. In recent months, the federal government has settled lawsuits securing more seats for disabled fans at Madison Square Garden in New York and at the nation’s largest college football stadium, at the University of Michigan.

The Justice Department acknowledged that some of the changes would have significant costs. But over all, it said, the value of the public benefits, estimated at $ 54 billion, exceeds the expected costs of $ 23 billion. In an economic analysis of the proposed rules, the Justice Department said the need for an accessible environment was greater than ever because the Iraq war was "creating a new generation of young men and women with disabilities". John L. Wodatch, chief of the disability rights section of the Justice Department, said:"Disability is inherent in the human condition. The vast majority of individuals who are fortunate enough to reach an advanced age will benefit from the proposed requirements.

Which of the following statement best summarizes the text()

A. Expensive Changes Proposed by Bush

B. Plan Seeks More Access for Disabled

C. The Revision of the Americans With Disabilities Act

D. Comments on the Governmental Proposal

问答题