题目

下面是宇航员 Jose Hernandez的采访页面。阅读该页内容,然后从方框中所给的A、B、C、D、E五个选项中选出符合各段内容的问题。 5 Questions for Jose Hernandez As a kid, he dreamed big dreams-- then worked hard to make them come true. We were farm workers. Until I was 12, my family movedaround every two or three months, following the harvest (丰收) of crops in California. That helpeddefine me I always work hard.It was December of 1972. I was 10, watching the finalApollo mission on a black-and-white TV. When I saw astronaut Gene Cernanwalking on 某小组为证明同温同压下,同浓度,同体积的酸性不同的两种二元酸与足量镁带反应时生成H2量相同而反应速率不同,装置如图.主要步骤如下:(1)配制浓度为0.5mol/L的硫酸和草酸溶液;(2)用______量取10.00mL0.5mol/L的硫酸和草酸溶液分别加入两锥形瓶中;(3)分别取去表面氧化膜的鎂带系于铜丝末端;(4)检查装置气密性,乙中装满水,按图连接好装置;(5)将铜丝下移,使足量鎂带浸如酸中(铜丝不与酸接触)至完全反应,同时记录______;(6)反应结束时,读取量筒内水体积ymL.将以上步骤补充完整并回答下列问题(1)(4)中如何检查气密性______;(2)用ρ=1.84  98.3%的浓硫酸配制250mL,c=0.5mol/L硫酸,主要仪器有______、______、烧杯、玻璃棒、酸式滴定管等;(3)读取量筒内水体积时,必须注意的问题是______;(4)简述速率不等的原因______,铜丝不能与酸接触的原因______;(5)此实验说明草酸为弱酸,请再设计一实验证明:______.
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