In this famous paper, Mendeleyev predicted: “We should still expect to discover many unknown simple bodies; for example, those similar to aluminum and silicon, elements with atomic weights of 65 to 75. ”
मेन्देलियेव यांनी १६ नवीन मूलतत्त्वांसाठी रिकाम्या जागा ठेवल्या.