Which scientist discovered the property atomic number that became the basis of the modern periodic law?

1. Mendeleev arranged elements by atomic mass, which left some anomalies. 2. In 1912 Henry Moseley discovered the property called atomic number. 3. Atomic number then became the basis of the modern periodic law. _Source: Samacheer Kalvi (TN SCERT) Class 10 Science, Unit 8 Periodic Classification of Elements "Modern Periodic Law", p.114_