1. The statement that is not true for the long form of the periodic table is
a) It reflects the sequence of filling electrons in the order of sub-energy levels s, p, d and f.
b) It helps to predict the stable valence states of the elements
c) It reflects trends in physical and chemical properties of the elements
d) It helps to predict the relative ionicity of the bond between any two elements
Explanation: It helps to predict the stable valence states of the elements
2. Which of the following pairs of atomic numbers represents elements belonging to the same group?
a) 11 and 20
b) 12 and 30
c) 13 and 31
d) 14 and 33
Explanation: 13 and 31
3. Which of the following sets of atomic number belong to that of alkali metals?
a) 1, 12, 30, 4, 62
b) 37, 19, 3, 55
c) 9, 17, 35, 53
d) 12, 20, 56, 88
Explanation: 37, 19, 3, 55
4.What is the atomic number of the next halogen if discovered?
Explanation: The atomic number 85 lies in the sixth period and since the next halogen, if discovered, will lie in the 7th period. Hence, its atomic number must be 85+32 = 117
5. All the elements of a group in the periodic table have the same
a) atomic weight
b) number of protons
c) mass number
d) number of electrons for bonding
Explanation: All the elements in a group have the same valence shell electrons.
6. The elements in which 4f orbitals are progressively filled up are called as
b) transition elements
Explanation: The elements in which 4f orbitals are progressively filled up are called as lanthanides
7. Which of the following is not a transition metal?
Explanation: Np is an-inner-transition element.
8. Which of the following have same number of electrons in the outermost orbit?
a) Pb, Sb
b) N, O
c) As, Bi
d) P, Ca
Explanation: As, Bi
9. Representative elements belong to
a) s- and p-blocks
b) p- and d-blocks
c) f-block only
d) d- and f-blocks
Explanation: Representative elements belong to s- and p-blocks
10. Element with atomic number 56 belongs to which block?
Explanation: s block