What are the units of specific gravity? Assuming that the density of water is 0.997 g.mL^-1 and the specific gravity of gold is 19.28 what is the density of gold in g.mL^-1? In pounds per cubic foot?

my attempt: no units for specific gravity. density of gold in g.ml^-1 = 19.2 g/mL^-1 i have no idea how to convert to pounds per cubic foot?

4. The mass of the earth is 6.1 x 10^27 g and the radius is 6.4 x 10^6 m. What is the average density of the earth in g.mL^-1? Hint the volume of a sphere is 4/3 pie r^3 where r is the radius of the sphere.

my attempt:
2.6 x 10^19 g/ml^-1

5 the mass of a neutron is 1.675 X 10^-24 g. The radius is about 10^-15 m. What is the density of a neutron in g.mL-1? What assumption is being made about the structure of the neutron in this calculation?

my attempt: 4.2 x 10^ -45
assume the structure is a sphere?

suppose you have a metal with a small volume (0.5mL) and a metal with a large volume (5.0mL). Which should give a higher percentage error if we use the water immersion method? explain.

my attempt: i would think less water would give a higher percentage error but not sure of the reasoning my guess the water not covering the metal throwing off the accuracy?