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【单选题】
用EDTA法测定自来水的硬度,已知水中含有少量Fe 3+ ,某同学用NH 3 ·H 2 O NH 4 Cl调pH=9.6,选铬黑T为指示剂,用 EDTA标准溶液滴定,溶液一直是红色的,找不到终点,这是由于( D )A.
pH太低
B.
pH太高
C.
指示剂失效
D.
Fe 3+ 封闭了指示剂
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【判断题】It is said that in every single day, the British drink about 165 million cups of tea. That is almost three cups per person.
A.
正确
B.
错误
【判断题】During the early years of the Second World War, the British Army suffered defeat in almost every theatre it deployed.
A.
正确
B.
错误
【判断题】It is said that in every single day, the British drink about 165 million cups of tea. That is almost three cups per person.
A.
正确
B.
错误
【单选题】听力原文： In the late eighteenth century, battles raged in almost every comer of Europe, as well as in the Middle East, South Africa, the West Indies, and Latin America. In reality, however, there was onl...
A.
The war in the Middle East.
B.
The war in South Africa.
C.
The war in Latin America.
D.
The war between Britain and France.
【判断题】Almost every British people thinks that to be truly British you have to be white.
A.
正确
B.
错误
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