Correct Answer:1 13.Which pair of atomic orbitals possess the same number of radial nodes? Correct Answer:Is and 3d 14.Which of the following is a hydrogen-like species? Correct Answer:He' 15.Which orbital is characterized by the quantum numbers n=3,1=0,m=0? Correct Answer:3s 16.In its ground state,an Hion has: Correct Answer:two spin-paired electrons 17.An element with a valence electron configuration of ns'np belongs to which group? Correct Answer:15 18.Br has two naturally occurring isotopes,approximately 50%each of"Br and 8Br.In the mass spectrum of naturally occurring dibromine,the parent ion will appear as: Correct Answer:three peaks with an approximate intensity ratio 1:2:1 19.In the emission spectrum of hydrogen,which series of emission lines falls in the visible region? Correct Answer:Balmer 20.The first ionization energy of Na is 496 kJ mol Give this value in eV if I eV =9.485 kJmol paying attention to significant figures. Correct Answer:5.14eV Correct Answer: 1 13. Which pair of atomic orbitals possess the same number of radial nodes? Correct Answer: 1s and 3d 14. Which of the following is a hydrogen-like species? Correct Answer: He+ 15. Which orbital is characterized by the quantum numbers n = 3, l = 0, ml = 0? Correct Answer: 3s 16. In its ground state, an H- ion has: Correct Answer: two spin-paired electrons 17. An element with a valence electron configuration of ns2 np3 belongs to which group? Correct Answer: 15 18. Br has two naturally occurring isotopes, approximately 50% each of 79Br and 81Br. In the mass spectrum of naturally occurring dibromine, the parent ion will appear as: Correct Answer: three peaks with an approximate intensity ratio 1 : 2 : 1 19. In the emission spectrum of hydrogen, which series of emission lines falls in the visible region? Correct Answer: Balmer 20. The first ionization energy of Na is 496 kJ mol-1. Give this value in eV if 1 eV = 96.485 kJ mol-1, paying attention to significant figures. Correct Answer: 5.14 eV