Matter can undergo changes internally while remaining electrically neutral because electrical neutrality refers to the balance between positive and negative charges within the matter.
For example, in a solid material like an iron bar, individual atoms consist of positively charged protons in the nucleus and negatively charged electrons orbiting around the nucleus. The number of protons in an atom determines its atomic number and defines its identity as an element.
During physical or chemical changes, the arrangement or distribution of atoms and/or electrons within the material may change. However, the total number of protons (positively charged) and electrons (negatively charged) remains the same, preserving the overall electrical neutrality of the material.
For instance, in a chemical reaction where atoms combine or rearrange to form new substances, the number of protons in the nucleus (which determine the element's identity) remains constant. Although electrons may be transferred or shared between atoms, the total positive and negative charges balance out, maintaining the material's electrical neutrality.
Similarly, in a physical change like melting or boiling, the arrangement of atoms may change as they transition from one phase to another (e.g., from solid to liquid), but the total number of protons and electrons remains unchanged, ensuring electrical neutrality.
In summary, changes can occur within matter without affecting its overall electrical neutrality because the total positive and negative charges remain balanced even if the arrangement or distribution of atoms and electrons changes.
