Mistake Master
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Mistake Master · AP Chemistry · Unit 3 · Step-Through Animation

One Photon at a Time

You'll learnthat one photon's frequency fixes its energy, while brightness only adds more photons.

A blinding red lamp and a dim ultraviolet one face the same sample, and only one of them knocks an electron loose. Light arrives in indivisible packets, and turning up the brightness sends more of them — never bigger ones. Eleven short steps; press Next for each one.

11 STEPS · 6 QUICK CHECKS · ENERGY PER PHOTON IN 10−19 J · v3

two lamps · one sample · energy arrives in packets
Before you start
What you're looking at
Two lamps facing one sample: a blinding red beam, and an ultraviolet one so dim you check that it is on.
The question
The bright red or the dim ultraviolet — which lamp knocks an electron loose?
Step 1 / 11