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（1 ）下列措施错误的是 （填序号）：①稀释浓硫酸时，将水缓慢注入浓硫酸中；②用熟石灰处理被酸污染的河水；③把鼻孔凑到容器口闻浓盐酸的气味④不慎将浓硫酸沾到皮肤上，立即用大量水冲洗，再3% ～5% 的碳酸氢钠溶液 （2 ）长江中学化学兴趣小组，用自制的酸碱指示剂对NaCl 、NaOH 、HCl 等溶液的酸碱性进行测定，结果记录如下： ①经过探究，发现 ___ 根本不宜作酸碱指示剂，这三种物质中理想的指示剂是 _____ 。 ②小明是一个勤思考，爱钻研的同学，发现了牵牛花瓣汁液遇NaOH 溶液变蓝色后，思考到了一个问题：NaOH 溶液中到底是哪种粒子使牵牛花汁液显蓝色呢？ 于是他和同学们继续探究： 【提出问题】NaOH 溶液中何种粒子使牵牛花汁液发生颜色改变？ 【提出猜想】猜想1 ：使牵牛花汁液变色的粒子是H 2 O 猜想2 ：使牵牛花汁液变色的粒子是 ____ 猜想3 ：使牵牛花汁液变色的粒子是 ____ 。 【设计实验】 【交流反思】实验完成后，继续讨论发现，还有更简单的方法，请你用文字或图示设计出更简单的方案： __
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【简答题】阅读理解。 A car needs gas to run and your body also needs food to work for you. Eating the right kind of food is very important. It can keep your body strong, so take care of what you eat. There are four ...
【简答题】A car needs gas to run and your body also needs food to work for you. Eating the right kind of food is very important. It can help your body grow strong to take care of what you eat. There are four ma...
【单选题】在有正三和弦的第一转位参与的正三和弦连接中,写作上三声部中的两个声部同时跳进(双跳)最需要注意的事项是?
A.
要保持平稳
B.
不要跳进
C.
根音、五音不要出现平行五度；
D.
不要出现反向五八度
【简答题】阅读理解。 A car needs gas to run and your body also needs food to work for you. Eating the right kind of food is very important. It can keep your body strong, so take care of what you eat. There are four ...
【单选题】The body also needs daily doses of sunlight to help ______ Vitamin D, crucial for maintaining body functions and for the health of muscles and bones.
A.
incorporate
B.
synthesize
C.
integrate
D.
assimilate
【单选题】There is no doubt that ________ a goal, one needs not only knowledge but also good personalities.
A.
realizes
B.
realizing
C.
being realized
D.
to realize
【单选题】China also needs to develop other types of energy resources and ( ) its sources of oil imports.中国也需要开发多种类型的能源并且使进口石油的来源多样化。
A.
drive
B.
diversal
C.
diverse
D.
diversify
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