问题 填空题

【10福建宁德16.】(15分)下图是化学实验室制取气体的常用装置。

(1)请写出图中标有①的仪器名称:               

(2)以下六种物质是初中教材中出现的化学物质,在一定条件下,都可以产生氧气。

请你写出上图中物质X的名称         ,实验室用该药品制取氧气的化学方程式为:       ,若要制取较纯净的氧气,则实验装置应选           (填标号)。

(3)实验室用B或C装置可制取     气体(填一种即可),制取该气体的化学方程式为          。装置B与C比较,B的优点是:               (写一点)。

(4)过氧化钠(Na2O2)固体在常温下与水反应也可以产生氧气,同时生成氢氧化钠。写出该反应的化学方程式:                                     

答案

(1)集气瓶

(2)高锰酸钾; 2KMnO4K2MnO4+MnO2+O2↑; A和E(或E和A)

(3)O2(或CO2或H2

2H2O22H2O+O2(或CaCO3+2HCl=CaCl2+H2O+CO2↑)

或Zn+H2SO4=ZnSO4+H2

控制反应速率(或节约药品)

(4)2Na2O2+2H2O=4NaOH+O2

分析根据实验室制取三大气体的原理、装置、收集方法解答.三大气体都可以用固液常温型装置制取.实验室制氧气有三种方法,发生装置有两种,固体加热型和固液常温型.收集装置根据气体的密度和溶解性选择.

解:(1)仪器名称集气瓶

(2)由实验室制氧气的几种方法可知物质X为高锰酸钾,高锰酸钾制氧气的化学方程式为:

2KMnO4K2MnO4+MnO2+O2↑氧气不易溶于水,可用排水法收集,密度比空气大,也可用向上排空气法收集,但排水法收集较纯,故装置选择为AE;

(3)装置B或C是固液常温型装置,反应物为固体与液体,条件为常温,因此可以用双氧水制氧气,实验室制氢气和二氧化碳都可以,化学方程式为:2H2O22H2O+O2(或CaCO3+2HCl=CaCl2+H2O+CO2↑或Zn+H2SO4=ZnSO4+H2↑)装置B用的是分液漏斗可控制反应速度;

(4)根据反应物与生成物可写出化学方程式为:2Na2O2+2H2O=4NaOH+O2

故答案为:(1)集气瓶

(2)高锰酸钾,2KMnO4K2MnO4+MnO2+O2↑,A(或E)和 E(或A)

(3)O2(或CO2或H2)2H2O22H2O+O2(或CaCO3+2HCl=CaCl2+H2O+CO2↑或Zn+H2SO4=ZnSO4+H2↑).

(4)2Na2O2+2H2O=4NaOH+O2↑.

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