In this instance, should the word be a noun or verb? I can tell it’s a noun because of the verb “had” that comes before it, in which case the correct usage would be “ effect.” UV light had no effect/affect on the reaction. “Affect” is definitely the correct word to use in this instance. The addition of salt did not influence the reaction.īingo.

The addition of salt did not affect the reaction. So the word needs to be a verb, which means you should use “ affect.' You can double-check by making the sure the word “ influence” could also be inserted into the sentence without changing its meaning.

In this instance, is the red text trying convey a thing or an action? The addition of salt did not effect/affect the reaction. So as you’re writing and you’re not sure whether to use the word “effect” or “affect,” just ask yourself, are you trying to use the word to convey a thing ( i.e., a noun) or an action ( i.e., a verb)? In scientific writing, these two rules virtually always apply. It means to be a result or a consequence of something.Ģ) The word “affect” is a verb (as in “to affect”). To use these words correctly, you only need to remember two things:ġ) The word “effect” is generally a noun. Scientists, lay-people, non-native and native English speakers alike tend to confuse the words “effect” and “affect” in their writing.

I can have that effect or affect