【单选题】以下哪项容量瓶的使用操作是错误的 ?
A.
容量瓶干燥时不能用火直接加热或烘烤,也不能放于烘箱中烘,一般倒置自然晾干,或用少量挥发性有机溶剂(如无水乙醇)荡涤,通风橱内挥干
B.
溶液转移至试剂瓶中的方法:先用少量溶液润洗试剂瓶 2-3 次,再转移溶液,最后应在试剂瓶上贴好标签,标签上至少需注明溶液名称、浓度、配制人、配制日期等
C.
容量瓶洗涤时,先用毛刷刷洗容量瓶内壁,至倒出水后内壁不挂水珠,即可用蒸馏水荡洗 3 次后备用
D.
溶液转移至容量瓶后,用少量蒸馏水洗涤烧杯及玻棒 3-4 次,洗涤液转入容量瓶
【多选题】2019 年 11 月 22 日,新奥股份 (600803.SH) 发布收购报告书,拟通过资产置换、发行股份及支付现金的方式向新奥国际及精选投资购买其持有的新奥能源合计 32.81% 股份。新奥股份的主要业务涵盖天然气生产与销售以及能源工程等天然气清洁能源上游业务,而标的新奥能源主要从事投资及建设、经营及管理燃气管道基础设施、车船用加气站及泛能站等下游业务,具有较强的协同的效应,本次重组后,新奥能...
【简答题】“We
are Ladies and Gentlemen serving Ladies and Gentlemen. ”这句名言出自( )。A. 康拉德·希尔顿 B. 凯撒·里兹 C. 凯蒙斯·威尔逊 D. 伊萨多·夏普
【单选题】在叠加发码方式的基础上进行改进,采用[ ],才能保证列车接收地面信息在时间和空间上的连续。
【简答题】How to ask for directions Do you have the experience of asking for directions? Most people do. Even men, who are said to have a good sense of direction, often have to ask for help. Here are some steps...
【简答题】How to Ask for Directions Do you have the experience of asking for directions? Most
people do. Even men, who are said to have a good sense of direction,
often have to ask for help. Here are some ste...
【简答题】什么是自锁控制?为什么说接触器自锁控制线路具有欠压和失压保护?
【单选题】听力原文:Good afternoon, ladies and gentlemen and welcome to Kahupata park. Before we begin today's tour, I'd like to make a few announcements. The South American exhibit is closed for cleaning and mainte...
A.
To explain the history of the place
B.
To inform. people about the crocodile
C.
To let people know about the schedule
D.
To describe the park tour