Answer to this is Radioactive isotopes.
Isotopes are the species of the same element having different atomic masses that means the number of protons remains the same but number of neutrons do differ. For example
and
are the two isotopes of Hydrogen (
).
Radioactive isotopes are the isotopes which release some kind of energy in the form of alpha particles, beta particles or gamma radiation. Examples of each of the decay processes are :
Alpha Decay: In this decay one alpha particle having atomic mass 4 and atomic number 2 or we can say a He molecule will come out. 
Beta Decay: In this decay a
particle is emitted increasing the atomic number of the reactant by 1 unit.

Gamma Radiation: In this type of reaction only radiation is emitted out which does not change the original molecule.

Answer:
Ionic equation:
Na⁺(aq) + OH⁻(aq) + H⁺(aq) + Cl⁻(aq) → H₂O(l) + Na⁺(aq) + Cl⁻ (aq)
Explanation:
Chemical equation:
NaOH(aq) + HCl(aq) → H₂O(l) + NaCl (aq)
Balanced chemical equation:
NaOH(aq) + HCl(aq) → H₂O(l) + NaCl (aq)
Ionic equation:
Na⁺(aq) + OH⁻(aq) + H⁺(aq) + Cl⁻(aq) → H₂O(l) + Na⁺(aq) + Cl⁻ (aq)
Net ionic equation:
OH⁻(aq) + H⁺(aq) → H₂O(l)
The Cl⁻(aq) and Na⁺ (aq) are spectator ions that's why these are not written in net ionic equation. The water can not be splitted into ions because it is present in liquid form.
Spectator ions:
These ions are same in both side of chemical reaction. These ions are cancel out. Their presence can not effect the equilibrium of reaction that's why these ions are omitted in net ionic equation.
Answer:
positive and negative
Explanation:
ik its prob not helpful now but ye sorry no ones answered lol
OA. It has liquid water
Explanation: Earth is the only planet (as of now) that has organic life, and has liquid water on the surface.
Hope this has helped you!