Interwoven are two objectives:  the development of skills related to the balance and the analysis of data, and the accumulation of evidence leading to the fundamental law of nature, the law of conservation of mass.

Experiment

2.1 The Mass of Dissolved Salt 

This observation raises the question of whether there is mass change when there is a change in volume.

2.2 Histograms 

Outline the reading and save in your lab notebook.

Experiment

2.4 The Mass of Ice and Water 

Make sure the lid on the container prevents atmospheric moisture from condensing inside the container during the melting.  Decide for yourself what to do about the condensation that may form on the outside of the container.  Construct a histogram of the class data.

Experiment

2.5  The Mass of Copper and Sulfur 

The purpose of this experiment is to show that mass is conserved even when a rather violent change takes place.  Again, we are not concerned with the chemical change as such.  We are concerned only with the effect the change has on the mass.

Experiment

2.6 The Mass of a Gas 

There are two important things to be learned in this experiment. First, mass does not change in a reaction that produces a gas, provided no gas is allowed to escape; this fact further builds up the evidence for conservation of mass.  Second, with the law of conservation of mass, we can account for the loss in mass when the gas is allowed to escape from the capped bottle in which it was generated; this shows that a gas has mass-a fact not appreciated for many years.

2.7 The Conservation of Mass 

Outline the reading in your lab notebook.

2.8 Laws of Nature