COD��Chemical Oxygen Demand��Ĝy��

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COD�Ĝy��

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��ˮ��м��һ��t��⛺ʹ߻��y,�ڏ��Խ��|(zh��)�мӟ��һ��r�g,��t��⛱�ˮ��п��|(zh��)߀ԭ,��၆�F�@�ζ�ʣ��t��,��(j��)��t��⛵��Ӌ��COD��ֵ.
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1.500mLȫ��b��.

2.�ӟ��b��(늠t).

3.25mL��50mL��ʽ�ζ��,�F��ƿ,��Һ��,��ƿ��.

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1.��t��⛘˜��Һ(c1/6K2Cr2O7=0.2500mol/L)

2.ԇ��F�`ָʾҺ

3.��၆�F�@�˜��Һ[c(NH4)2Fe(SO4)2•6H2O≈0.1mol/L]��ʹ��ǰ�˶��

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��၆�F�@�˶� :�ʴ_��ȡ10.00mL��t��⛘˜��Һ��250mL�F��ƿ��,��ˮϡ��110mL��,��10mL��,�u��.��s��,��3��ԇ��F�`ָʾҺ(�s0.15mL),��၆�F�@��Һ�ζ�,��Һ��ɫ��Sɫ��(j��ng)�{�Gɫ��t��ɫ��K�c.
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ȡ20mLˮ��,��10mL��t��⛣��ϻ��b��,��ټ��30mL��y,�ӟ�� 2h

��s��,��90.00mLˮ�_ϴ��ܱ�,ȡ��F��ƿ.

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�y��ˮ�ӵ�ͬ�r,ȡ20.00mL��sˮ,��ͬ�Ӳ��E��հ׌��.ӛ䛵ζ��հוr��၆�F�@�˜��Һ��.
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CODCr(O2,mg/L)=8×1000(V0-V1)•C/V

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1��ʹ��0.4g��ṯ�j(lu��)��x�ӵ��_40mg,��ȡ��20.00mLˮ��,��߿ɽj(lu��)��2000mg/L��x�ӝ�ȵ�ˮ�ӡ��x�ӵĝ��^��,��Ҳ��ټ��ṯ,��ʹ��ṯ:��x��=10:1(W/W)��F(xi��n)��Ȼ��,��Ӱ표y��,��

2��ڻ��W(xu��)��С��50mg/L��ˮ��,��(y��ng)��0.0250mol/L��t��⛘˜��Һ,��صΕr��0.01mol/L��၆�F�@�˜��Һ,��
3,��ˮ�Ӽӟ��Һ��t��ʣ��(y��ng)��1/5—4/5��,��

4,��⛘˜��Һ�z��ԇ��|(zh��)��Ͳ��g(sh��)�r��ÿ��⛵��ՓCODCr��1.176g,��ܽ�0.4251g��(HOOCC6H4COOK)��sˮ��,��D(zhu��n)��1000mL��ƿ,��sˮϡ��˾��ʹ֮�ɞ�500mg/L��CODcr�˜��Һ,��Õr��,��

5��CODCr�Ĝy��Y(ji��)��(y��ng)��λ��Ч��(sh��)��,��

6,��ÿ�Ό��r��(y��ng)��၆�F�@�˜ʵζ��Һ�M�И˶�,��Ҝ��^�ߕr��ע��ȵ�׃��,��

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