问题
问答题 简答题
酚二磺酸光度法测定水中硝酸盐氮时，水样若有颜色应如何处理？
答案
参考答案：
每100ml水样中加入2ml氢氧化铝悬浮液，密塞充分振摇，静置数分钟澄清后，过滤，弃去最初的20ml滤液。
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酚二磺酸光度法测定水中硝酸盐氮时，水样若有颜色应如何处理？
参考答案：
每100ml水样中加入2ml氢氧化铝悬浮液，密塞充分振摇，静置数分钟澄清后，过滤，弃去最初的20ml滤液。
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