Homework 1
1. A common method for testing gold for purity is to measure its density by weighing it in air and then in water. In an era of rising gold prices, a swindler proposed to make a fake gold ingot by using a hollow slab of iridium (density 22.5 g / cm^3) and plating it with a thin layer of gold. To make a fake ingot of total mass 0.5 kg, what should be the total volume? What is the volume of the interior air space?
2. Calculate the density of the solid material (the material other than water) in soybeans whose mass is 13% water. Average kernel density in this state is 1.232 g / cm^3.
3. The specific gravity of an unknown substance is 2.16. Identify the unknown substance and state its density in lb / ft^3.