Which of the following particles is the heaviest?
Meson
Electron
Proton
Neutron
When the speed of an electron increases, the specific charge.
Decreases
Increases
Remains same
None of these
Number of neutrons in a heavy hydrogen atom is.
0
1
2
3
Mass number of an atom represents the number of.
Protons only
Protons and neutrons
Protons and electron
Neutrons and electrons
Which of the following electronic configurations represents a noble gas?
2, 8, 2
2, 8 ,6
2, 8
2, 8, 8, 2
Elements having 7 electrons in the valence shell are called.
Halogens
Chalcogens
Alkali metals
Alkaline earths.
The firmness with which an electron is held by an atom is a measure of its.
Electronegativity
Ionisation potential
Ionic character
Metallic character
Mass of an electron is.
9.1 × 10-28g
9.1 × 10-25g
9.1 × 10-10g
9.1 × 10-18g
Which of the following statements is not true?
Most of the space in an atom is empty
The total number of neutrons and protons is always equal
The total number of electrons and protons in an atom is always equal
The total number of electrons in any energy level can be calculated by the formula 2n2
The halogen with smallest electron affinity is
Fluorine
Chlorine
Bromine
Iodine
