Hello there! According to Aristotle, ethos equates to ethics and pathos equates to emotion.
When dealing with ethos/logos/pathos remember: ethos appeals to ethics, pathos appeals to emotion, and logos appeals to logic. To remember this, I usually look at the first three letters of each word:
ethos = ethics
logos = logic
With pathos you can't really use this same method, but if you already know the other two pathos should be easy! I hope I could help you today, and have a great rest of your day! ☺