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Question
Find the correlation:
Mendeleev’s periodic table : atomic mass : : Modern periodic table : _______
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Solution
Mendeleev’s periodic table : atomic mass : : Modern periodic table : atomic number
Explanation:
Mendeleev organised his periodic table based on the atomic mass of elements. In contrast, the modern periodic table is based on the atomic number (the number of protons), which Henry Moseley demonstrated to be a more fundamental property for predicting periodic trends in chemical behaviour.
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