Laboratorio N°3: La tabla periódica

Chemistry Laboratory Practice Overview

In this chemistry laboratory practice session, the instructor demonstrates experiments involving the properties of metals like magnesium, sulfur, copper, zinc, and lead. Various reagents and equipment are used to explore chemical reactions and determine properties such as acidity and density.

Determining Properties of Magnesium

• The first experiment aims to determine the properties of magnesium by adding a piece of magnesium ribbon to a beaker with distilled water.

• Observing that magnesium does not react immediately with water; subsequently, a Bunsen burner is lit to create a non-luminous blue flame for further testing.

• After burning the magnesium ribbon in the flame, the resulting ashes are collected in a test tube and mixed with distilled water to form magnesium hydroxide.

• Testing the solution's acidity by adding an indicator; observing a color change to crimson indicates it is basic (magnesium hydroxide).

Investigating Properties of Sulfur

• The second experiment involves heating sulfur over a Bunsen burner flame in a test tube sealed with a one-hole stopper.

• Adding distilled water after heating sulfur forms an acidic oxide; confirming its acidity using an indicator like methyl orange turning red.

Experimental Determination of Metal Densities

• The third experiment focuses on determining experimental densities of three metals - copper (reddish), zinc (silver), and lead (dark gray).

• Measuring mass using an analytical balance and volume displacement method with water in a graduated cylinder for each metal to calculate density.

• Conducting similar procedures for zinc and lead to ascertain their densities through mass-volume relationships.

New Section

In this section, the speaker discusses the importance of precise measurements in a scientific experiment involving lead and a beaker.

Measuring Lead Volume

• The measurement must be exact and precise.

• Slide the pre-determined lead along the walls of the beaker on a balance.

• Record the final volume obtained in the notebook.