1. The word atom is derived from a Greek word
(A) Atomos
(B) Basic
(C) Demos
(D) Particle
2. The mass of electron is ______ times 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) Neutron
(B) Nucleon
(C) Anti-nucleon
(D) Hypron
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 electrons is maximum is called
(A) Band
(B) Orbit
(C) Axis
(D) Radius
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) 8
(C) 7
(D) 9
9. The periods in the periodic table are
(A) 7
(B) 6
(C) 8
(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 called
(A) Lines
(B) Groups
(C) Periods
(D) Series
12. Modern periodic law is based on
(A) Neutron number
(B) Atomic mass
(C) Atomic number
(D) Nucleons
13. The valency of all elements present in same group is
(A) Different
(B) Multiples
(C) Variable
(D) Same
14. The blocks in the periodic table are
(A) 1
(B) 2
(C) 4
(D) 3
15. Atomic size in a group from top to bottom
(A) Increases
(B) Decreases
(C) Remains same
(D) Uncertain
16. Until now ______ elements have been discovered
(A) 109
(B) 110
(C) 111
(D) 112
17. The smallest particle of an element that takes part in chemical reaction is
(A) A compound
(B) A molecule
(C) Radical
(D) An atom
18. The mass of a neutron is ______ kg
(A) 9.11 × 10⁻³¹
(B) 1.67492 × 10⁻²⁷
(C) 1.6726 × 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) Polymers
(B) Isobars
(C) Isomers
(D) Isotopes
20. The maximum number of electrons in an orbit is given by formula
(A) 2n¹
(B) 2n³
(C) 2n²
(D) 2n⁴