COMPOUNDS- 2D Givers/ Takers        Name_______________ ____________________
      I.M.S.EARTH & SPACE SCIENCE

      Class-Earth & Space                 Period: ________  Date __/__/__                

COMPOUNDS- 2D:

     How do elements join to form compounds?

            Atoms can join together by giving up electrons, gaining electrons, or by sharing some of their electrons. In this activity you will use models of  atoms to show how some compounds are made. The arrowheads and slots on the models show how many electrons are involved when the atoms form compounds.

Materials: Paper / Pencil/ Scissors / Tape

Procedure:

1. Carefully cut out each of the paper models on the other page.
2.  Make one model of Ca, S, and C. Make two models each for Na, Al, and H. Make three models of O and four models of Cl.
3. Models of various compounds can be made by fitting the arrows on some models into the openings of others (please see the Calcium Chloride example).
4. All the openings and arrows must be used to make a compound.
5. Number and tape all completed models to this paper and label with correct formula arrived at below.

Conclusions:

Make models of the compounds listed. Write the correct molecular formula for each compound.

1. Calcium oxide:           ________________
2. Sodium oxide: ________________
3. Sodium sulfide:           ________________
4. Hydrogen sulfide:      ________________
5. Aluminum chloride: ________________
6. Water:                        ________________
7. Sodium chloride:        ________________
8. Aluminum oxide:        ________________
9. Carbon dioxide:          ________________
10. Carbon tetrachloride: ________________

Bonus:

Make up a compound for extra credit and give the correct formula.

11. __________________: ________________