Elements are different due to different number of……..
a) Electron
b) Neutrons
c) a &b both
d) Protons
When atomic number was discovered ?
a) 1912
b) 1916
c) 1913
d) 1915
Atom is electrically………..
a) positive
b) negative
c) neutral
d) none of these
Atomic Number is represented by the symbol.
a) A
b) N
c) Z
d) M
Who discovered atomic number ?
a) Dalton
b) Moseley
c) Rutherford
d) Bohr
Carbon has its atomic number………
a) 6
b) 8
c) 7
d) 5
