<h2>Atoms whose atomic number are the same but whose mass numbers are different are called : Isotopes </h2>
Explanation:
Isotopes
They are the elements with same atomic number but different mass number .
for example : Protium , deuterium and tritium are isotopes of hydrogen .
: C-14 and C-12 are isotopes of oxygen .
: Cl-35.5 and Cl-37 are isotopes of chlorine
Alpha particles
They are helium nuclei with +2 unit charge and 4 a.m.u mass
They are represented as : He₂⁴.
Ions
The atom carrying charge is called as ion .
It can be of two types : Cation and anion
cation :atom with positive charge
Anion : atom with negative charge
Beta particles
They are actually particles with charge and mass of electron and is represented as :₀ e⁻¹
The answer is the last one (it needs a medium through which to travel) it is not true about radiation. A radiation is the emission of energy in the form of waves or particles through space or through a material medium. This includes; electromagnetic radiation, such as a radio wave, microwaves, visible light, x rays, and gamma radiation.
Acid Rain is formed when chemicals in the air get into rain and up the acidity levels!!!!!!
Hope this helps guys!