Question

1. where are transition metals found in the periodic table?
2. what 3 properties of transition metals would make them valuable for use in coins?

c. properties of nonmetals and important nonmetal groups

1. list 4 properties of nonmetals.
2. oxygen and chlorine exist as diatomic elements. what does this mean?
3. list all the elements in the halogens group.
4. why are halogens so reactive? how does reactivity change as you go down the group?
5. why are noble gases so unreactive?

d. metalloids

1. what are metalloids? list all the metalloids on the periodic table.

Explanation:

1. Transition metals are found in groups 3 - 12 of the periodic table.
2. Three properties of transition metals that make them valuable for coins are: high luster (gives them an attractive appearance), good malleability (can be shaped easily), and relatively high resistance to corrosion (coins last longer).
3. Four properties of non - metals are: poor conductors of heat and electricity, brittle (if solid), usually have low density, and tend to gain electrons in chemical reactions.
4. Diatomic elements are elements that exist as molecules made up of two atoms. So oxygen ($O_2$) and chlorine ($Cl_2$) exist as pairs of atoms.
5. The elements in the halogens group are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).
6. Halogens are very reactive because they have 7 valence electrons and need only 1 more to achieve a stable octet. As you go down the group, reactivity decreases because the atomic size increases, making it harder for the nucleus to attract an additional electron.
7. Noble gases are unreactive because they have a full outer shell of electrons (either 2 or 8), which gives them a stable electron configuration.
8. Metalloids are elements that have properties intermediate between metals and non - metals. The metalloids on the periodic table are boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), and polonium (Po).

Answer:

1. Groups 3 - 12 of the periodic table.
2. High luster, good malleability, relatively high resistance to corrosion.
3. Poor conductors of heat and electricity, brittle (if solid), low density, tend to gain electrons in chemical reactions.
4. They exist as molecules made up of two atoms (oxygen as $O_2$ and chlorine as $Cl_2$).
5. Fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At).
6. They have 7 valence electrons and need 1 more to achieve a stable octet; reactivity decreases as you go down the group.
7. They have a full outer shell of electrons, giving them a stable electron configuration.
8. Elements with properties intermediate between metals and non - metals; boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), polonium (Po).