Mystery
Powders from Mars INTRODUCTION In this
lab you will test and try to identify the physical and chemical properties of
several unknown powder. This lab will
test your skills in terms of your ability to carefully test the chemicals to
see what happens to them. You will
then need to take all the information you gather and match the properties to
the chemical list below. One of these powders has a link to a mysterious
powder from mars, listen in class for the explanation. PROCEDURE The following is the list of
chemical/physical properties of the chemicals that you will use.
Based on the tests that your group will do in this lab
you should be able to guess the name of the unknown white powder that you
started with. If your group conducts the
test carefully the table that your group crested should match the table above
very closely. Heating of the chemicals will be done in this lab so
extra careful safety measures will be required when doing this lab. Be sure and follow all the directions. Iodine Testing
Place a
several drops of iodine on each of the mystery powders. Use a spot plate for
this process. Major changes with iodine will involve color. Changes in texture may also happen but are
not usually as visible. Iodine testing
is dangerous. Iodine is a poison. Heat Testing Place a small
sample of the powder on the heating surface.
When instructed to do so apply heat to the heating surface and observe
the changes. Changes in color and texture should be seen on some of the
powders. Look for changes in state as
well. Acid Testing Apply
several drops of acid to the different powers. This is done in the same way as the iodine
test using the spot plates. Acid can be
dangerous so be careful as you use this chemical. Observe any changes in the powders. Water Testing In this test
you are looking to see if the powder will dissolve in water or not. Follow the class instructions as to how to
properly test for solubility. PH Testing
Tests the
Parts of Hydrogen in a chemical. Chemicals that test above 7 are considered
to be BASE chemicals, chemicals that test below
seven are considered ACIDS. Chemicals that test at or slightly around seven
are considered to be neutral. (generally water should be neutral) The Ph test
needs to be done in the solution that was created from the water test. |