I think it is A. produces the hydrogen ion
Hmm trick question here's my answer: the content: protons charge the electrons into its usage , the size: 1.6fm if I'm wrong sorry if I'm right: HA IN YOUR FACE HA!!!
When a substance is heated, it gains thermal energy. Therefore, its particles move faster and its temperature rises. When a substance is cooled, it loses thermal energy, which causes its particles to move more slowly and its temperature to drop.
Answer:
Speed, 
Explanation:
The device which is used to accelerate charged particles to higher energies is called a cyclotron. It is based on the principle that the particle when placed in a magnetic field will possess a magnetic force. Just because of this Lorentz force it moves in a circular path.
Let m, q and V are the mass, charge and potential difference at which the particle is accelerated.
The work done by the particles is equal to the kinetic energy stored in it such that,

v is the speed with which the particles enter the cyclotron
So,

So, the speed with which the particles enter the cyclotron is
. Hence, this is the required solution.
Answer:
Helium has atomic mass 4.002602.
So the answer to yr question is helium.