A sample of gold weighs 1.2 oz. The sample is pounded into a thin rectangular sheet with an area of 400. sq. ft. The density of gold is 19.3 grams per cm3. What is the thickness of the foil in centimeters?Given: 28.35 g = 1 oz, 1 ft = 12 inches, 1 inch = 2.54 cm

thickness of the gold sheet = 4.74 * 10⁻⁶ cm

Explanation:

mass of gold sample = 1.2 oz,; area of rectangular gold sheet = 400 sq. ft

Converting mass of gold from oz. to g

1 oz. = 28.35 g

mass of gold sample in grams = 1.2 * 28.35 g = 34.02 g

Converting from feet to cm;

1 feet  =  12 * 2.54 cm = 30.48 cm

1 sq. ft = (30.48)² = 929.0304 cm²

area of gold in cm² = 400 * 929.0304 cm² = 371612.16 cm²

Since the density of a solid is constant

Density = mass/volume

Volume = mass/density

where volume =area * thickness

therefore, area * thickness =mass/density

thickness = mass/(density * area)

substituting the value; thickness = 34.02 g/(19.3 gcm⁻³ *371612.16 cm²)

thickness of the gold sheet = 4.74 * 10⁻⁶ cm

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.