4. Model Question Paper

Choose the correct answers :

Q1. Rutherford’s alpha-particle scattering experiment was responsible for the discovery of :

(A) Atomic Nucleus

(B) Electron

(C) Proton

(D) Neutron

Ans : (A) Atomic Nucleus

Q2. Isotopes of an element have

(A) the same physical properties .

(B) different chemical properties .

(C) different number of neutrons

(D) different atomic numbers .

Ans :  (C) different number of neutrons

Q3. The number of valence electrons in  ion are :

(A) 16

(B) 8

(C) 17

(D) 18

Ans : (D) 18