General
✓✗Alpha particles are emitted by radioactive elements like
- Radium
- Polonium
- Both ‘a’ and ‘b’
- None of these
General
✓✗An atom of an element ‘X’ is written as 
, what does the number 12 represents?
, what does the number 12 represents?- atomic number
- atomic radius
- atomic mass
- number of electrons & protons
General
✓✗Relative mass of a proton is
-
gms
- 1 u
-
gms
- 2 u
General
✓✗Number of valence electrons in chloride ion is
- 7
- 8
- 2
- 6
General
✓✗Valency of Nitrogen is
- +1
- +2
- +3
- -3
General
✓✗Neutron was discovered by
- Thomson
- Goldstein
- Rutherford
- Chadwick
General
✓✗Atomic number of Argon is 18, the number of valence electrons is
- 2
- 8
- 16
- 4
General
✓✗Which equation explains mass number correctly?
- Mass number = atomic mass
- Mass number = atomic number + number of neutrons
- Mass number = number of protons + number of neutrons
- All are correct
General
✓✗Which shell of an atom can hold a maximum of 18 electrons?
- 2nd
- 3rd
- 4th
- 5th
General
✓✗Mass number is equal to
- Number of protons + electrons
- Number of protons + neutrons
- Number of electrons + neutrons
- Number of electrons + neutrons + Protons