(i) 1s 2 2s 2 2p 6 3s 1 (ii) 1s 2 2s 2 2p 6 3s 2 (iii) 1s 2 2s 2 2p 6 3s 2 3p 1 (iv) 1s 2 2s 2 2p 6 3s 2 3p 4 (v) 1s 2 2s 2 2p 6 3s 2 3p 5 The electron configuration of the atom that is expected to have a positive electron affinity is ________.