a) 0 b)1 c) 2 d) 3 e) 4 14. How many unpaired electrons are in the ground state of a C atom? 15. Which of the ollowing elements is chemically most similar to the one that has a ground state electron co 1s22s1? b) Co c) C d) Cs e) Cr the second ionization 16. The second ionization energy of Mg isthan its first ionization energy, and is energy of Na a) higher, higher than d) lower, lower eredder, bluer b) lower, higher c) higher, lower 17. Which of the following elements has the smallest ionization energy? a) He b) Ne c)Ar d) Kr e 18. Which of the following elements is most electronegative? a) N b)O c)F d) S e) 19. In which of the following atoms do the valence electrons experience the greatest effective nuclear charge? a) K b) Ca c) Ge d) Br e) Kr 20. Which quantum number defines the shape of an orbital? a)n b)l c) m d)ms e)s 21. Which quantum number defines the orientation of an orbital? a)n b) c)m d) ma e)s 22. Which quantum number defines the distance from the nucleus? a) nb c) m d) m e)s 23. Which quantum number defines the property of the electron called \'spin\"? a)nb) c m dme)s Solution kindly ask the questions separately and not all at once 14)c 2 1s2 2s2 2p2 is the ground state electronic configuration of C. The two electrons in the p oribtal are unpaired 15)d Cs. the element is lithium. Cesium (Cs) is in the same group as Litium and hence chemically most similar to it. 16) c Higher, lower. The second ionization energy of Mg is larger than the first because it always takes more energy to remove an electron from a positively charged ion than from a neutral atom. ( ie the electrons are more tightly held by the nucleus) It is however lower than the second ionization energy of Na because after losing 1 electron Na has a noble gas configuration which is very stable and hence it is more difficult to remove the second electron 17 e Xe Xenon has the lowest ionisation energy due to its largest size which makes it easier to remove the outermost electron. .

1. a) 0 b)1 c) 2 d) 3 e) 4 14. How many unpaired electrons are in the ground state of a C atom? 15.
Which of the ollowing elements is chemically most similar to the one that has a ground state
electron co 1s22s1? b) Co c) C d) Cs e) Cr the second ionization 16. The second ionization
energy of Mg isthan its first ionization energy, and is energy of Na a) higher, higher than d)
lower, lower eredder, bluer b) lower, higher c) higher, lower 17. Which of the following
elements has the smallest ionization energy? a) He b) Ne c)Ar d) Kr e 18. Which of the
following elements is most electronegative? a) N b)O c)F d) S e) 19. In which of the following
atoms do the valence electrons experience the greatest effective nuclear charge? a) K b) Ca c) Ge
d) Br e) Kr 20. Which quantum number defines the shape of an orbital? a)n b)l c) m d)ms e)s 21.
Which quantum number defines the orientation of an orbital? a)n b) c)m d) ma e)s 22. Which
quantum number defines the distance from the nucleus? a) nb c) m d) m e)s 23. Which quantum
number defines the property of the electron called 'spin"? a)nb) c m dme)s
Solution
kindly ask the questions separately and not all at once
14)c 2
1s2 2s2 2p2 is the ground state electronic configuration of C. The two electrons in the p oribtal
are unpaired
15)d Cs. the element is lithium. Cesium (Cs) is in the same group as Litium and hence
chemically most similar to it.
16) c Higher, lower. The second ionization energy of Mg is larger than the first because it always
takes more energy to remove an electron from a positively charged ion than from a neutral atom.
( ie the electrons are more tightly held by the nucleus)
It is however lower than the second ionization energy of Na because after losing 1 electron Na
has a noble gas configuration which is very stable and hence it is more difficult to remove the
second electron
17 e Xe Xenon has the lowest ionisation energy due to its largest size which makes it easier to
remove the outermost electron.