A negative ion or anion is an electrically charged atom or group of atoms that are formed by gaining one or more electrons. Whereas a positive ion or cation is an electrically charged atom or group of atoms that are formed by losing one or more electrons.
The losing and gaining all occurs on the outermost shell.
The answer would be B, an electron because the proton is positive, neutron is neutral, and the nucleus is the center of the atom.
"The water becomes warmer."
<u>Remember</u>: Kinetic energy means how much, on average, a molecule is moving around. This is directly translated into heat. Therefore, the higher the kinetic energy, the more heat produced.