"Chemistry and Society Crossword": HTML5 Crossword

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4. What AQI color is used for "very unhealthy"? (6)
6. Which gas is known as the "silent killer"? (6,8)
9. What level of the atmosphere has the "bad ozone"? (11)
10. Is Sulfur a Metal, Metalloid, or a Nonmetal? (8)
12. Most elements are? (6)
13. What is silicon's atomic number? (8)
14. Is thallium a metal, nonmetal, or metalloid? (5)
15. What is the last element in period 5? (5)

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1. What is the last element in group 8B? (6)
2. Is NaCl a element, compound, or mixture? (8)
3. Is He an element or compound? (7)
5. What is the common name for the chemical family 8A? (5,3)
7. What does AQI stand for? (3,7,5)
8. What is it called when there is a substance composed of two or more separate elements? (8)
11. What is a substance that is made of entirely from one type of atom? (7)