某同学为验证海带中含有碘，拟进行如下实验，请回答相关问题。
(1)第1步：灼烧。操作是将足量海带灼烧成灰烬。该程中使用的主要仪器是______（填代号）。
A．试管
B．瓷坩埚
C．烧杯
D．量筒
(2)第2步：I-溶液的获取。将海带灰转移到小烧杯中，向其中加入蒸馏水，搅拌煮沸，然后的操作是______。
(3)第3步：氧化。下列氧化剂最好选用______（填代号）。
A．浓硫酸
B．新制氯水
C．KMnO4溶液
D．H2O2
理由是__________。
(4)第4步：碘单质的检验。操作是取少量第(3)步的溶液，滴加_______溶液，如果溶液显蓝色，则证明海带中含碘。
(1)B
(2)冷却、过滤
(3)D；不引入其他杂质
(4)淀粉
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| It was a Sunday afternoon and, unlike the past few weekends, the four of us did not sit at the kitchen table playing cards. That evening, my parents seated my sister Emily 1 I down in the living room because they said that they 2 to talk to us. My father began slowly, as if he was 3 something back. 4 grew deep in his forehead 5 he told us that he and my mother were getting a divorce. Tears began to 6 in my mother's eyes. My father went over and stared out 7 the view of the backyard. I always 8 of my parents as being in love, 9 they fought all the time. I saw them as 10 in every way. I looked up to them 11 anyone else, and now they destroyed their 12 . I think the 13 came from not having anyone to look up to. Now I see my father about once a week, and it is 14 . I can talk to him more 15 and I have learned to appreciate the time I get to spend with my father. 16 my mother it has changed in a different way. I have 17 to respect her more. She works so hard to 18 the family. It took lots of time for me to know that what they did was for the 19 and to 20 them for it. I now know that parents are not perfect and also make mistakes. | ||||
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