Question

q.3. identify the following elements as metals, nonmetals, or metalloids using the periodic table.
hydrogen (h): nonmetal silicon (si):
helium (he): chlorine (cl):
lithium (li): calcium (ca):
boron (b): krypton (kr):
oxygen (o): antimony (sb):
aluminum (al): gold (au):

Explanation:

Classify elements using periodic table positions: metals (left/center), nonmetals (right/group 18), metalloids (stair-step between metals/nonmetals).

Answer:

Hydrogen (H): nonmetal
Helium (He): nonmetal
Lithium (Li): metal
Boron (B): metalloid
Oxygen (O): nonmetal
Aluminum (Al): metal
Silicon (Si): metalloid
Chlorine (Cl): nonmetal
Calcium (Ca): metal
Krypton (Kr): nonmetal
Antimony (Sb): metalloid
Gold (Au): metal