The properties of substances and their bonding

Assessed criteria: Criterion C - Processing and Evaluating

Level descriptor

7-8

The student is able to: i. correctly collect, organize, transform and present data in numerical and/ or visual forms ii. accurately interpret data and explain results using correct scientific reasoning iii. evaluate the validity of a hypothesis based on the outcome of a scientific investigation iv. evaluate the validity of the method based on the outcome of a scientific investigation v. explain improvements or extensions to the method that would benefit the scientific investigation.

 

 

Objective

To study, evaluate and compare the properties of several substances and relate them to their type of bonding (ionic, covalent or metallic).

Theoretical background

The properties of substances are related to the kind of bonding present in those substances. The type of bonding depends on the atoms present and is related to their position in the periodic table.

Materials

Substances A to D                             Conductivity meter

Test tubes                                          Distilled water

Spatula                                                           Acetone

Bunsen burner

Method

Repeat the procedure for each of the substances provided:

1.    Take ½ a spatula of the substance in a test tube. Describe the appearance of the substance.

2.    Gently heat it in the flame of the Bunsen burner and state if the approximate melting point. (Low, intermediate or high).

3.    Take ½ a spatula of the substance in another test tube.

4.    Add 10 mL water, stir it and state whether the substance is soluble in water or not.

5.    Repeat the steps 4 and 5 using acetone instead of water.

6.    Using the conductivity meter, state if the substance is a conductor in solid state.

7.    If it the substance is soluble in water, test whether the solution is a conductor or not.

Blog tasks

The whole report must be posted to your group blog. Make sure you include:

1.    A table of results.

2.    The type of bonding present in each substance.

3.    A secondary table to show “expected” results. (Research the type of bonding and the expected results for the test that you carried out)

4.    A conclusion comparing the actual results with the expected results.

5.    An evaluation that suggest improvements that could be made to your method.

6.    A minimum of 2 references (APA format).