1. What is the chemical bond?
2. What is the function of the chemical bond?
3. What types of chemical bonds do you know?

Acetylsalicylic  acid,  also  known as  aspirin,  is  an  acetyl  derivate  of salicylic acid,  which is a  weak white  and crystalline  acidic  substance, that has a  melting point of  135-137oC.

LEARNING OBJECTIVES
? to define a chemical change
? to recognize a chemical change and distinguish it from a physical one
? to read a chemical equation
? to write chemical equations
? to balance chemical equations
? to classify chemical reactions
? to write formation and combustion reactions for given compounds.
? to recognize the limitant reactant
? to make stoichiometric calculations:
from mass to moles, from moles to mass, yield, masses needed for complete reactions (from a given quantity of a reactant)

AIMS:
To revise and extend students’ knowledge of butyric carbohydrates
To systemize students’ knowledge of butyric carbohydrates
To put into practice the acquired knowledge of the structure, isomerism and chemical properties of the butyric carbohydrates
To illustrate the connection between the carbohydrates by means of chemical reactions
To develop students’ thinking and imagination by means of different logical operations- synthesis, analysis, comparison, analogy

An acidic solution is any aqueous solution which has a pH< 7.0 ([H+] > 1.0 x 10-7 M). A basic solution is an aqueous solution containing more OH-ions than H+ions. An aqueous solution with a pH greater than 7.

Procedures:
1.Students are given the definitions of Group and Period s.
2.They are taught systematic variying features at the Periodic Table.
3.Groups of A and B and their features are told.