Why should the mass of an object never be determined while the object’s temperature is above room temperature? If you weigh a hot object on the balance, the reading will be higher, the same, or lower than if it had been weighed after it cools to room temperature?

ACTIVITY OF WET LABS MEASURING THE MASS & VOLUME OF OBJECTS AND SUBSTANCES

Describe how to use the “difference method” when performing mass determinations. Why are masses in the chemistry laboratory usually determined by the difference method (using a beaker to contain the object to be weighted, rather than just placing the object directly on the pan of the balance)

Why should the mass of an object never be determined while the object’s temperature is above room temperature?

If you weigh a hot object on the balance, the reading will be higher, the same, or lower than if it had been weighed after it cools to room temperature?

Why should liquids never be poured on or near the balance?

Results and Observations
A. Determining the mass of the solid object
Description of the object:
Description of Container A:
Trial 1 Trial 2 Trial 3
Mass of Container A
Mass of Container A and the Solid Object
Mass of the Solid Object __
Average Mass of the Solid Object
Mass of the Solid Object (w/o difference method)
B. Determining the Mass of a Granular Solid
Description of the Granular Solid:
Description of Container B:
Trial 1 Trial 2 Trial 3
Mass of Container B
Mass of Container B and the Granular Solid
Mass of the Granular Solid
Average Mass of the Granular Solid
C. Determining the Mass of a Liquid
Trial 1 Trial 2 Trial 3
Mass of Container C
Mass of Container C and the Water
Mass of the Water
Average Mass of the Water
* Upload one picture for each part of the lab (A, B, and C) with your report sheet
Post-Laboratory Questions
After determining the mass of the Solid Object using the difference method, you tared the balance with the Container A on it, then placed the Solid Object into Container A to determine its mass. Did the resulting mass determination agree with that determined using the difference method? Explain why your results do or do not make sense.

Why is it important always to use the same balance during the course of an experiment? Explain using examples from your own data.