Answer
Atoms in a gas are electrically neutral. Atoms in a plasma are ionized, i.e., they've been stripped of one or more electrons and are are now positively charged ions.
Work Step by Step
This is discussed on page 276.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.