~ないうちに focuses more on unfavorable results
知らないうちに、家の前にあるラーメン屋が潰れていた。 Before I knew it, the ramen shop in front of my house went out of business. (which is not nice)
前に is more general
食べる前に、手を洗わなくてはいけない。 Before you eat, you need to wash your hands.
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~ないうちに focuses more on unfavorable results
知らないうちに、家の前にあるラーメン屋が潰れていた。 Before I knew it, the ramen shop in front of my house went out of business. (which is not nice)
前に is more general
食べる前に、手を洗わなくてはいけない。 Before you eat, you need to wash your hands.