问题 实验题

下表是某城市某日空气质量报告:

某研究性学习小组对表中首要污染物SO2导致酸雨的成因进行探究。(提示:SO2是一种无色、有刺激性气味的有毒气体,易溶于水,具有与CO2相似的化学性质)

【探究实验】实验一:用下图所示装置进行实验。

(1)A装置的作用是__________SO2气体。

(2)实验过程中,B装置内石蕊试纸的颜色没有发生变化,C装置内湿润的蓝色石蕊试纸变红色,说明SO2与水反应生成一种_________________。

(3)D装置的作用是__________,发生反应的化学方程式是______________。

实验二:往盛有水的烧杯中通入SO2气体,测所得溶液的pH______7(填“>”“=”或“<”),然后每隔1小时测定其pH,发现pH逐渐变小,直至恒定,说明烧杯中溶液被空气中的氧气氧化最终生成H2SO4。 【查阅资料】SO2形成酸雨的另一途径:SO2与空气中的O2在飘尘的作用下反应生成SO3(飘尘的质量和性质在反应前后不发生变化),SO3溶于降水生成H2SO4。在此过程中飘尘作______________。

【探究结论】SO2与空气中的氧气、水反应生成硫酸而形成酸雨。该市可能易出现酸雨。

【模拟实验】(1)由于食醋和酸雨的酸度(pH)差不多,因此酸雨对大理石的作用可以通过大理石碎片放在醋中来模拟。当把2.0g大理石碎片放在醋中一整夜后,取出固体干燥称重,其质量可能是(醋酸钙易溶于水)__________。A.小于2.0g B.正好2.0g C.大于2.0g

(2)这组学生还做了另一个实验,即将大理石碎片放在蒸馏水中过夜,其实验的目的是_____________。

【知识联想】SO2具有与CO2相似的化学性质,根据下图给出的SO2及其化合物问的相互转化关系回答:X的化学式是_____,写出X与Na2SO3反应的化学方程___________________,反应类型是__________。

答案

实验一:(1)干燥

(2)酸

(3)吸收SO2,防止污染空气SO2+2NaOH==Na2SO3+H2O

实验二:<;催化剂

(1)A

(2)与实验作对照,证明对大理石起腐蚀作用的是醋酸而不是水;

【知识联想】H2SO3;H2SO3+2NaOH==Na2SO3+2H2O;复分解反应(或中和反应)

单项选择题
单项选择题

Passage Two

In the 1920s, the pioneers of artificial intelligence (AI) predicted that, by the end of this century, computers would be conversing with us at work and robots would be performing our housework. But as useful as computers are, they are nowhere close to achieving anything remotely resembling these early aspirations for humanlike behavior. Never mind something as complex as conversation: the most powerful computers struggle to reliably recognize the shape of an object, the most elementary of tasks for a ten-month-old kid.

A growing group of AI researchers think they know where the field went wrong. The problem, the scientists say, is that AI has been trying to separate the highest, most abstract levels of thought, like language and mathematics, and to duplicate them with logical, step-by-step programs. A new movement in AI, on the other hand, takes a closer look at the more roundabout way in which nature came up with intelligence. Many of these researchers study evolution and natural adaptation instead of formal logic and conventional programs. Rather than digital computers and transistors, some want to work with brain cells and proteins. The results of these early efforts are as promising as they are peculiar, and the new nature-based AL movement is slowly but surely moving to the forefront of the field.

Imitating the brain’s neural network is a huge step in the right direction, says computer scientist and biophysicist Michael Conrad, but it still missed an important aspect of natural intelligence. "People tend to treat brain as if it were made up of color-coded transistors. " He explains, "But it’s not simply a clever network of switches. There are lots of important things going on inside the brain cells themselves." Specifically, Conrad believes that many of the brains’ capabilities stem from the pattern-recognition proficiency of the individual molecules that make up each brain cell. The best way to build an artificially intelligent device, he claims, would be to build around the same sort of molecular skills.

Right now, the notion that conventional computers and software are fundamentally incapable of matching the processes that take place in the brain remains controversial. But if it proves true, then the efforts of Conrad and his fellow AI rebels could turn out to be the only game in town.

The new trend in AI research stems from ().

A.the shift of focus of study onto the recognition of the shapes of objects

B.the belief that human intelligence cannot be duplicated with logical, step-by-step programs

C.the aspirations of scientists to duplicate the intelligence of a ten-month-old child

D.the efforts made by scientists in the study of the similarities between transistors and brain cells