The modern periodic table is based on the periodic law proposed by:
A. John Dalton
B. Henry Moseley
C. Dmitri Mendeleev
D. Niels Bohr
Answer: Option B
Solution (By JKExamLibrary)
Henry Moseley discovered that the atomic number (number of protons) is the fundamental property of an element, not atomic mass. He proposed the modern periodic law: properties are periodic functions of atomic numbers. Mendeleev's law was based on atomic mass, which had anomalies.
Explanation:
From Faraday's first law, m = ZQ, so Z = m/Q. SI unit is kg/C, but practical unit is g/C. It is the mass of substance liberated per unit charge.
Explanation:
Iodine directly converts from solid to violet vapor on gentle heating (sublimation). NaCl melts; sugar decomposes; copper melts at high temperature. Other sublimable substances: camphor, naphthalene, dry ice.
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