Calculate the Percent Loss in mass

Question

A clean dry porcelain crucible was weighed on an analytical balance and found to have a mass of 4.6587 grams. A sample of the iron-oxalate complex, mass 0.5977 gram, was placed in the crucible and heated in an oven at 75 degrees C until the sample reached a constant mass. At this point, the crucible and contents weighed 5.1787 grams. Calculate the percent loss in mass of the iron-oxalate complex upon heating. This is the percent water in the complex.

I would appreciate it if someone could please show me how to do this!?

Thanks!!

Answer 1

Given:

Mass of crucible: 4.6587 g

Mass of complex: 0.5977 g

Mass of dried complex + crucible: 5.1787 g.

Calculation:

Mass of dried complex = 5.1787 g - 4.6587 g = 0.5200 g

Mass lost from complex = 0.5977 g - 0.5200 g = 0.0777 g

Percent mass lost = 100% * 0.0777 g / 0.5977 g = 13.0%.