# Structure of Atom Mock Test-1

Question No:1
14C isotope of carbon will have

(a) 14 electrons
(b) 9 protons and 5 neutrons
(c) 6 protons and 8 neutrons
(d) 8 protons and 6 neutrons

Question No:2
The set of isotopic nuclei is

$_{6}^{12}C , _{7}^{14}N , _{8}^{16}O$

$_{6}^{12}C , _{6}^{14}C ,_{6}^{13}C$

$_{6}^{14}C , _{7}^{15}N ,_{8}^{16}O$

$_{6}^{12}C , _{6}^{13}N , _{6}^{14}O$

Question No:3
The number of electrons and neutrons of an element is 18 and 20 respectively. Its mass number is

(a) 18
(b) 38
(c) 20
(d) 37

Question No:4
atch the following:
Column-I           Column-II
A. Thomson          P. X ray discovery
C Rutherford          R. Mass of a torn was assumed to be uniformly distributed over the atom
D. Henri Becquerel           S. Nucleus discovery

(a) A – R, B-S, C – P, D – Q
(b) A – P, B-R. C – Q, D – S
(c) A – P, B –R, C – S, D – Q
(d) A – R, B-P, C – S, D- Q

Question No:5
Two atoms are said to be Isobars if

(a) they have same atomic number but different mass number.
(b) they have same number of neutrons but different number of electrons.
(c) they have same number of neutrons but different number of protons.
(d) sum of the number of protons and neutrons is same but the number of protons is different.

Question No:6
Match the following:
Column-I
A Isotope
B. Isobar
C Isotone
D. Isoelectronic
Column-II

$_{36}^{86}Kr , _{39}^{89}Y$

$_{53}^{127}I , _{53}^{131}I$

$_{21}Sc^{3+} , _{17}Cl^-$

$_{19}^{40}K , _{16}^{40}S$

(a) A – (iii), B – (iv), C – (ii) D (i)
(b) A– (ii), B (iv), C- (i) D – (iii)
(c)A– (ii) , B (i), C– (iv), D- (iii)
(d)A- (iii), B-(ii), C-(i), D – (iv)

Question No:7
Which of the following contains as pair of isotopes?

$_{24}^{52}X , _{24}^{55}X$

$_{25}^{52}X , _{26}^{52}X$

$_{26}^{56}X^{2+} , _{24}^{56}X^{3+}$

$_{25}^{55}X^{3+} , _{23}^{53}X$

Question No:8

Assertion:
X-rays are used to study the interior of the objects

Reason:
X- rays are not deflected by the electric and magnetic fields and have a very high penetrating power.

(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) Both A and R are false

Question No:9

Assertion:
During Rutherford’s scattering experiment few positively charged α particles were deflected.

Reason:
The positive charge of the atom is spread throughout the atom.

(a) Both A and R are true and R is die correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false
(d) Both A and R are false

Question No:10

Assertion:
An electron in an orbit will emit radiation that comes from electronic motion and In only 10-8 S it will spiral into the nucleus.

Reason:
Charged particles when accelerated should emit radiation according to the electromagnetic theory of Maxwell

a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false
(d) Both A and R are false

Question No:11
The number of electrons, protons and neutrons in a species is 17,14 and 14 respectively. The appropriate symbol for the species is

$_{14}^{17}C^{3-}$

$_{14}^{28}N^{3-}$

$_{14}^{31}O^{2-}$

$_{28}^{56}N^{3-}$