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【单选题】
用标准对比法测定某一未知溶液浓度时,测得标准溶液和未知浓度溶液的吸光度分别为 0.18和0.24,已知标准溶液的浓度为2.4×10 -4 mol/L,则未知液的浓度(mol/L) 是( )
A.
1.0×10 -4
B.
1.5×10 -4
C.
1.8×10 -4
D.
3.2×10 -4
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