Density and Specific Gravity Concepts

Study Notes

Density and Specific Gravity Concepts

Oil floats on water due to its lower density; oil density is 0.92 g/mL compared to water's 1.00 g/mL.
Heating air in a hot air balloon causes it to expand, resulting in a decreased density, enabling the balloon to rise.

Comparison of Density and Specific Gravity

Density measures mass per unit volume; specific gravity compares the density of a substance to the density of water (1.00 g/mL).
Specific gravity has no units because the units of density cancel out in the ratio:
- Density = mass of substance / volume of substance
- Specific gravity = density of substance (g/mL) / density of water (1.00 g/mL)

Density Calculation Example

For an object with a mass of 18.4 g and a volume of 11.2 mL, density is calculated as:
- Density = mass / volume = 18.4 g / 11.2 mL = 1.64 g/mL

Specific Gravity Calculation Example

For the same object (mass 18.4 g, volume 11.2 mL), specific gravity is calculated as:
- Specific gravity = density of the substance (1.64 g/mL) / density of water (1.00 g/mL) = 1.64

Determining Sinking or Floating

An object with a density greater than that of water (1.64 g/mL) will sink when placed in water.

Volume Calculation from Mass and Density

For a 15.0 g liquid with a density of 0.875 g/mL:
- Volume = mass / density = 15.0 g / 0.875 g/mL = 17.1 mL

Mass Calculation from Volume and Density

For the same liquid with a density of 0.875 g/mL in a volume of 34.6 mL:
- Mass = density x volume = 0.875 g/mL x 34.6 mL = 30.3 g

Description

This quiz covers the fundamentals of density and specific gravity, explaining their definitions and calculations. It includes examples such as the behavior of oil and water, as well as practical calculations for both density and specific gravity. Test your understanding and application of these essential physical science concepts.