20. 7 elements that always occur in pairs in nature HONClBrIf
23. Unreactive elements of Group 8A of the periodic table
31. a substance that cannot be separated or broken down into simpler substances by chemical means.
32. electron that do not participate in chemical reactions
8. equivalent to the charge on an atom or an ion
26. According to the modern theory a region in an atom where there is high probability of finding electrons
23. Unreactive elements of Group 8A of the periodic table
31. a substance that cannot be separated or broken down into simpler substances by chemical means.
32. electron that do not participate in chemical reactions
8. equivalent to the charge on an atom or an ion
26. According to the modern theory a region in an atom where there is high probability of finding electrons