Question

getting to know the periodic table
how often do i make chemistry jokes?
...periodically
across

1. the number of protons plus the number of neutrons equals the
2. the group 17 elements
3. columns on the periodic table
4. elements 58 - 71
5. the group 1 elements
6. mercury and bromine are the only elements that naturally exist in this state at room temperature
7. these subatomic particles have no charge
8. semi - conductors; boron, silicon, and arsenic are examples

down

1. elements 90 - 103
2. carbon, sulfur, oxygen, and nitrogen are all examples of
3. located at the center of the periodic table
4. these metals are located in group 2
5. the group 18 elements
6. rows on the periodic table
7. these elements are shiny and excellent conductors of heat and electricity
8. these subatomic particles have a negative charge
9. these subatomic particles have a positive charge

Explanation:

1. Across - 1: The sum of protons and neutrons gives the mass number.
2. Across - 2: Group 17 elements are halogens.
3. Across - 3: Columns on the periodic table are groups.
4. Across - 4: Elements 58 - 71 are lanthanides.
5. Across - 5: Group 1 elements are alkali metals.
6. Across - 6: Mercury and bromine are liquids at room - temperature.
7. Across - 7: Neutrons are subatomic particles with no charge.
8. Across - 8: Boron, silicon, and arsenic are metalloids (semi - conductors).
9. Down - 9: Elements 90 - 103 are actinides.
10. Down - 10: Carbon, sulfur, oxygen, and nitrogen are non - metals.
11. Down - 11: Transition metals are located at the center of the periodic table.
12. Down - 12: Group 2 elements are alkaline earth metals.
13. Down - 13: Group 18 elements are noble gases.
14. Down - 14: Rows on the periodic table are periods.
15. Down - 15: Metals are shiny and good conductors of heat and electricity.
16. Down - 16: Electrons are subatomic particles with a negative charge.
17. Down - 17: Protons are subatomic particles with a positive charge.

Answer:

1. Across - 1: Mass number
2. Across - 2: Halogens
3. Across - 3: Groups
4. Across - 4: Lanthanides
5. Across - 5: Alkali metals
6. Across - 6: Liquids
7. Across - 7: Neutrons
8. Across - 8: Metalloids
9. Down - 9: Actinides
10. Down - 10: Non - metals
11. Down - 11: Transition metals
12. Down - 12: Alkaline earth metals
13. Down - 13: Noble gases
14. Down - 14: Periods
15. Down - 15: Metals
16. Down - 16: Electrons
17. Down - 17: Protons