What is the difference between ions and isotopes

Ions are elements that are charged, for example Cl- is an ion because it has gained an electronic to become negative and to have a full outer shell of electrons (8 electrons) because of the octect rule. Other examples are Mg2+ and Al3+, which have lost elections to become positive.

An isotope is an element that has the same number of Protons and Electrons, but a diffent number of Neutrons. Because of this, the relative atomic mass of the element changes for example, Carbon. On the periodic table, the relative atomic mass is 12. However isotopes of carbon could be Carbon-14 or Carbon-16. This is because the number of neutrons has increased and so is an isotope of Carbon-12. Isotopes occur naturally and the most common isotope of carbon is Carbon-12. All isotopes of elements have the same properties, only difference is the neutron number

Neurotransmitters are messengers responsible for communication between neurons. they are released from synaptic vesicles and are received by receptors.  the communication is referred to as neurotransmission. the following statement is true about neurotransmitters: a. they're stored in synaptic vesicles in the axon.