Question

1. Which quantum number gives information about the shape of an orbital ?

   		angular quantum number (l)
   		magnetic quantum number ( ml )
   		principal quantum number ( n)
   		spin quantum number ( ms )

1. How many unpaired electrons are in S ?

   		0
   		1
   		2
   		3

1. What is the ground state electron configuration of Cr ?

   		1s2 2s2 2p6 3s2 3p6 4s1 3d5
   		1s2 2s2 2p6 3s2 3p64s2 3d1 4p4
   		1s2 2s2 2p6 3s2 2p6 3s2 3p6 4s2 3d4
   		1s2 2p6 3s2 3p6  4s1 3d5

1. What is the ground state electron configuration of P^3- ?

   		1s2 2s2 2p6
   		1s2 2s2 2p6 3s1 3p6
   		1s2 2s2 2p63p6 4s2
   		1s2 2s2 2p6 3s2 3p6

1. What is the formula of cyanide ion ?

   		CNO-
   		CN-
   		CO32-
   		CCl3-

1. Which one of the following explains London dispersion forces ?

   		an attraction between H bound to a N, O, F to a N, O, or F
   		the forces of attraction between polar compounds
   		forces of attraction between molecules due to the formation of instantaneous dipole forces

1. What is the change in internal energy of a system which does 40 kJ on the surroundings and releases 20 kJ of heat ?

   		- 20 kJ
   		+20 kJ
   		-60 kJ
   		+60 kJ

Answer 1

Ans is Q.3. What is the ground state electron configuration of Cr? Ground state electron configuration of cr Is² 2s²2p38² 3p6 45' 3ds According to aufbau ruke first electron fithe the electronic Configuration should be 1s² 25² 2po 38² 3p6 49² 3d", But Cr an exception. So only goes in Is orbital and ite electronic configuration becomes 1s² as² apo 36² 3p6 4s 3ds Qu. What grounde State election configuration in us orbital them 3d. So 1 electron the of p² ? ? Ans. 15 ) Atomic number of Phosphorous P is So there are 15 electrons in P. Bid in p3, three extra electron comes total electious dine p3- ir 18. And ite electronic configuration 15² 25² 2p 3s² 3p6 ou

W = 40 KJ So and کم 20kJ AU (+20 + 40) KJ 20K is +20kJ So change in internal energy in