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Course: High school chemistry > Unit 1

Lesson 4: The periodic table and Lewis diagrams
Science
High school chemistry
Atoms, elements, and the periodic table
The periodic table and Lewis diagrams
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Problem

Elemental phosphorus exists in a red form that is used to ignite matches. But the phosphorus isn’t in the head of the match, it’s on the striking surface!
A lit match
The striking surface of a matchbox contains red phosphorus
In which period of the periodic table would you find phosphorus?
Choose 1 answer: