Question

1. what element is located in

a. group 2, period 5?
b. group 16, period 4?
c. group 3a, period 2?
d. group 5b, period 5?

1. list three elements named after countries
2. list three elements named after scientists (and name the scientists)
3. list three elements named after planets
4. list five elements whose names do not match their symbols
5. what is the only letter that does not appear on the periodic table (in name or symbols)?
6. which two families of elements often combine to form salts? (group 1 and 17)
7. what makes the elements in the halogen group reactive? give an example of a halogen. what form do they usually come in? (diatomic, need 1 more to fill)
8. why are the noble gases so unreactive? they have full outer shells, making them stable
9. list five properties of most transition metals. good conductivity, high melting point, soft in form, shiny, malleable
10. what makes metalloids different from the transition metals? what is their primary use? not metals but have properties of both. primarily use as semiconductors
11. compare and contrast the lanthanides and the actinides. lanthanides: shiny, reactive. actinides: radioactive, nuclear power
12. what does it mean for an element to be \synthetic\? made artificially in a lab, not found naturally
13. what does it mean for an element to be radioactive? unstable nuclei that decay, releasing radiation

Explanation:

1a. Using the periodic - table layout, elements in Group 2, Period 5 is strontium (Sr).
1b. In Group 16, Period 4, the element is selenium (Se).
1c. Group 3A, Period 2 contains boron (B).
1d. Group 5B, Period 5 has niobium (Nb).

1. Examples of elements named after countries are francium (France), germanium (Germany), polonium (Poland).
2. Elements named after scientists: curium (Marie and Pierre Curie), einsteinium (Albert Einstein), fermium (Enrico Fermi).
3. Elements named after planets: mercury (Mercury), uranium (Uranus), neptunium (Neptune).
4. Elements with non - matching names and symbols: iron (Fe), copper (Cu), silver (Ag), gold (Au), tungsten (W).
5. The letter 'J' does not appear in the name or symbol of any element on the periodic table.

Answer:

1a. Strontium (Sr)
1b. Selenium (Se)
1c. Boron (B)
1d. Niobium (Nb)

1. Francium (France), Germanium (Germany), Polonium (Poland)
2. Curium (Marie and Pierre Curie), Einsteinium (Albert Einstein), Fermium (Enrico Fermi)
3. Mercury (Mercury), Uranium (Uranus), Neptunium (Neptune)
4. Iron (Fe), Copper (Cu), Silver (Ag), Gold (Au), Tungsten (W)
5. J