1. The word atom is derived from a Greek word
(A) Particle
(B) basic
(C) demos
(D) atomos
2. The mass of electron is ____ times of the mass of proton
(A) 1/1834
(B) 1/1840
(C) 1/1838
(D) 1/1836
3. All the particles present in the nucleus are called
(A) nucleon
(B) hypron
(C) Anti-nucleon
(D) Neutron
4. The proton was discovered by
(A) Goldstein
(B) J.J. Thomson
(C) Dalton
(D) Chadwick
5. The atomic number is represented by
(A) A
(B) M
(C) N
(D) Z
6. The region around the nucleus where probability of finding the electrons is maximum is called
(A) radius
(B) band
(C) axis
(D) orbit
7. The maximum number of electrons in ‘s’ orbital is
(A) 1
(B) 3
(C) 2
(D) 4
8. The groups present in the periodic table are
(A) 6
(B) 7
(C) 8
(D) 9
9. The periods in the periodic table are
(A) 6
(B) 8
(C) 7
(D) 9
10. The vertical columns in periodic table are called
(A) Periods
(B) series
(C) lines
(D) groups
11. The horizontal rows in periodic table are
(A) Periods
(B) groups
(C) lines
(D) series
12. Modern periodic law is based on
(A) nucleons
(B) atomic mass
(C) Neutron number
(D) Atomic number
13. The valency of all the elements present in same group is
(A) same
(B) multiples
(C) variable
(D) Different
14. The blocks in the periodic table are
(A) 1
(B) 2
(C) 3
(D) 4
15. Atomic size, in a group from top to bottom
(A) remain same
(B) decreases
(C) Increases
(D) uncertain
16. Until now ____ elements has been discovered
(A) 109
(B) 110
(C) 112
(D) 111
17. The smallest particle of an element that takes part in chemical reaction is
(A) radical
(B) a molecule
(C) An atom
(D) a compound
18. The mass of a neutron is, Kg
(A) 9.11 × 10⁻³¹
(B) 1.6726 × 10⁻²⁷
(C) 1.67492 × 10⁻²⁷
(D) 1.67492 × 10⁻²⁸
19. The atoms of the same element having same atomic number but different mass number are called
(A) isomers
(B) isobars
(C) Isotopes
(D) polymers
20. The maximum number of electrons in an orbit is given by formula
(A) 2n¹
(B) 2n²
(C) 2n³
(D) 2n⁴