(a) 39.5 g
(b) 49.53 cm^3
(c) 0.7975 g/cm^3, liquid is an alcohol
(a) This will be the difference between the weight of the iron in air and the weight submerged in fluid. So:
390.0 g - 350.5 g = 39.5 g
(b) The density of iron is 7.874 g/cm^3, so the volume of the iron chunk is
390.0 g / 7.874 g/cm^3 = 49.53 cm^3
(c) The density of the fluid will be the mass of the fluid divided by the volume, so:
39.5 g / 49.53 cm^3 = 0.7975 g/cm^3
Since the density is very dependent upon the temperature and since the temperature wasn't specified, the actual substance can't be completely identified. Although some candidates are:
1. Mixture of Alcohol and water. Density ranges from 0.785 g/cm^3 to 1.000 g/cm^3.
2. Crude oil. Density 0.790 g/cm^3
3. Hydrazine. Density 0.795 g/cm^3
4. Methanol. Density 0.791 g/cm^3
5. Ocimene. Density 0.798 g/cm^3
The most likely candidate is a high concentration of an alcohol of some sort.
