Match these items with their correct definitions.

1 .
baking soda
last two horizontal rows on the Periodic Table
2 .
shell
elements to the left of the “stair-steps” in the Periodic Table
3 .
water
elements to the right of the “stair-steps” in the Periodic Table
4 .
nonmetals
hold the secret to chemical change
5 .
rare earth elements
path or orbit in which electrons whirl about nucleus
6 .
electrons
a common base
7 .
metals
H 2 O