分光光度计做定量分析的理论依据是( )。
A. 欧姆定律
B. 朗伯-比尔定律
C. 库伦定律
D. 等物质的量反应规则
测定某一符合朗伯-比尔(Lambert一Beer)定律的有色溶液的吸光度时,用厚度为1.0cm的比色皿,测得其吸光度为0.13。若其浓度保持不变,改用2.0cm的比色皿在相同条件下进行测定,则其吸光度为:
A. 0.065
B. 0.26
C. 0.13
D. 0.52
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A. Proposal made at a surprise party.
B. Proposal made by using quite a lot of money.
C. Proposal made by means of an object flying in the sky.
D. Proposal made in front of a large crowd.
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A. They had had a quarrel.
B. They had skated on the ice.
C. They had had a bad experience in winter.
D. They had enjoy a wonderful time together.
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