This unique set demonstrates the relationship of protons in the formation of acids and bases. Included are: Teacher's Guide and reproducible student masters, as well as 3 packets of model material. Each packet contains 20 hydrogen atom centers, 3 oxygen atom centers, 3 halogen (chlorine)atom centers, 2 carbon atom centers, 3 nitrogen atom centers and 20 bonds, Grades 6-12. Shipped directly from the manufacturer. Not available with rush shipping. Delivery time estimated at 10-14 days or less. Gift wrap not available. Information on how to place your order by fax or by telephone. Product Number AARACB