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Course: High school chemistry > Unit 1

Lesson 5: Periodic trends
Science
High school chemistry
Atoms, elements, and the periodic table
Periodic trends
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Apply: ionization energy trends

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You might need: Periodic table

Problem

Pure selenium exists in three colors: gray, red, and black. The electrical conductivity of the gray form can be changed by shining light on it. For this reason, selenium was used as a light detector for almost 100 years.
Black and red selenium
The gray and red forms of selenium
Which of the following has a larger ionization energy than Se?
Choose 1 answer: