Interpret the following equations in terms of 1- Numbers of representative particles(atoms and molecules).
2- Moles.
3- Masses of reactants and produces.
4- Volumes

1) Al2S3 2Al + 3S

2) C4H12 + 7O2 6H2O + 4CO2

3) Cl2 + 2KBr 2KCl + Br2

Which common material is an example of a polymer? (25 pts) a. steel b. plastic c. petroleum d. rubbing alcohol

Name the element in group 17, period 2. (periodic table)

Pastoral farming is best described as a. a method of raising livestock and moving herds b. an african method of agriculture c. a method of cultivating crops on poor soils d. a common method of desert farming select the best answer from the choices provided a b c d