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问题 推断题

（8分）纳米碳酸钡是一种重要的无机化工产品，下图是某厂生产纳米碳酸钡的工艺流程．请答下列问题：

（1）试剂A的化学式为   ，操作1和操作2的名称是   ，若在实验室中进行该操作，实验中玻璃棒的作用是    。

（2）操作3为   和   。

（3）写出向氯化钡溶液加入氢氧化钾并通入二氧化碳时发生反应的化学方程式

                   ，                 。

（4）该流程中的副产物可用作     。（写一种用途）

答案

（1）HCl  过滤   引流         （2）洗涤   干燥（或烘干）

（3）2KOH+CO2=K2CO3+H2O       K2CO3+BaCl2=BaCO3↓+2KCl

（4）钾肥或化肥

题目分析：(1)因为加入试剂A，产生了二氧化碳，试剂A的化学式为HCl，经过操作1和操作2，得到了不溶性固体和液体，故为过滤操作，若在实验室中进行该操作，实验中玻璃棒的作用是引流

(2)因为经过过滤操作后得到BaCO3固体，固体表面可能沾有KCl或BaCl2等其他的杂质，为保证得到纯净的BaCO3固体，所以要洗涤，然后再干燥

(3) 向氯化钡溶液加入氢氧化钾并通入二氧化碳时发生反应的化学方程式：2KOH+CO2=K2CO3+H2O       K2CO3+BaCl2=BaCO3↓+2KCl

（4）操作2经过过滤得到KCl溶液，这种副产物可用作钾肥或化肥

多项选择题

鼠疫耶尔森菌的理化特征包括（）

A.鼠疫耶尔森菌为两端钝圆，两极浓染的椭圆形小杆菌

B.革兰染色阴性

C.无鞭毛，有芽胞，能活动

D.对外界抵抗力较弱，对干燥、热和一般消毒剂均甚敏感

E.在蚤粪中存活1个月，在尸体中可活数周至数月
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单项选择题

Lobbying groups often try to disguise a financial self-interest by clumsily dressing up their arguments in the guise of concern for the public. You see this tendency in the pharmaceutical industry (21) in energy and lumber companies who like to tout their (22) of the environment. But (23) , two new books argue, are these tactics more (24) a cause for concern than in agribusiness.
Marion Nestle’s "Food Safety: Bacteria, Biotechnology, and Bio-terrorism’ looks at the way the American meat and biotechnology industries have (25) successfully on Capitol Hill (26) stricter federal regulation, which the author argues has undermined the safety of the food supply.
(27) , Maxime Schwartz’s "How the Cows Turned Mad" (28) the origins of mad-cow disease over more than two centuries, and reveals the fallout from the British government’s blind (29) that the disease could not be (30) to humans.
In 1999, Ms Nestle writes in her earlier book, Rosemary Mueklow, the executive director of the National Meat Association, lobbied against President Clinton’s (31) to establish a more thorough testing regime for E. coli 0157: H7, a potentially (32) pathogen.
Ms Muck low’s organization—which represents meatpackers and processors who (33) to discard or reprocess meat found to be infected under the new testing regime—argued on Capitol Hill that (34) microbial testing in meat could actually lead to a greater public health risk (35) confident consumers might relax their own safe-handling procedures at home.

A. dead B. deadly C. live D. lively
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