Yes, that is correct! When an atom loses one or more electrons, it becomes positively charged. This is because electrons have a negative charge, so losing them means that there are more positive charges (protons) than negative charges (electrons). A common example of this is sodium (Na), which loses an electron to form a sodium ion (Na+).
On the other hand, when an atom gains an electron, it becomes negatively charged. This occurs because the additional electron adds a negative charge to the atom, resulting in more negative charges than positive charges. A well-known example is chlorine (Cl), which gains an electron to become a chloride ion (Cl–).
The process of one atom donating an electron and another atom receiving it often occurs to help fulfill the octet rule, where atoms seek to have eight electrons in their outer shell for stability. For instance, you could have sodium and chlorine reacting, where sodium donates its one outer electron to chlorine, allowing chlorine to fill its outer shell.
In summary, losing an electron gives an atom a positive charge, while gaining an electron results in a negative charge. This electron transfer is a fundamental concept in chemistry widely observed in ionic bonding.