# Specific gravity and mass relationship

### How Are Density, Mass & Volume Related? | Sciencing

Specific gravity is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a In scientific work, the relationship of mass to volume is usually expressed directly in terms of the. Gauge Pressure & Absolute Pressure: Relation & Conversion . We measure density in mass per unit volume which is written using measures. An introduction to density, specific gravity and specific weight - formulas with The Imperial (U.S.) units for density are slugs/ft3 but pound-mass per cubic foot .. The relations between volume, pressure, temperature and quantity of a gas.

Scales are often employed to determine the mass of a substance since weight is a function of mass and gravity. Since gravity is very nearly the same over the surface of the Earth, weight becomes a good indicator of mass. Increasing and decreasing the amount of material measured increases and decreases the mass of the substance.

Volume Volume describes how much space a substance occupies and is given in liters SI or gallons English. The volume of a substance is determined by how much material is present and how closely the particles of the material are packed together. As a result, temperature and pressure can greatly affect the volume of a substance, especially gases.

As with mass, increasing and decreasing the amount of material also increases and decreases the volume of the substance. For example, 10 grams of freshwater has a volume of 10 milliliters.

### How to Convert Specific Gravity in Weight | Sciencing

Unlike mass and volume, increasing the amount of material measured does not increase or decrease density. This makes density a useful property in identifying many substances.

**Density and Specific Gravity**

However, since volume deviates with changes in temperature and pressure, density can also change with temperature and pressure. Specific Gravity One derivative measurement of density is specific gravity. Specific gravity compares the density of a substance with the density of a reference material.

- Specific gravity

In the case of gases, the reference material is standard dry air, or air without water. In the case of liquids and solids, the reference material is fresh water. Specific gravity is calculated by dividing the density of a substance by the reference substance's density. For example, gold has a density of Where the specific gravity of the sample is close to that of water for example dilute ethanol solutions the correction is even smaller. Digital density meters[ edit ] Hydrostatic pressure-based instruments This technology relies upon Pascal's Principle which states that the pressure difference between two points within a vertical column of fluid is dependent upon the vertical distance between the two points, the density of the fluid and the gravitational force.

## Mass, Volume and Specific Gravity

This technology is often used for tank gauging applications as a convenient means of liquid level and density measure. Vibrating element transducers This type of instrument requires a vibrating element to be placed in contact with the fluid of interest.

The resonant frequency of the element is measured and is related to the density of the fluid by a characterization that is dependent upon the design of the element. In modern laboratories precise measurements of specific gravity are made using oscillating U-tube meters. These are capable of measurement to 5 to 6 places beyond the decimal point and are used in the brewing, distilling, pharmaceutical, petroleum and other industries.

The vibrating fork immersion probe is another good example of this technology. This technology also includes many coriolis-type mass flow meters which are widely used in chemical and petroleum industry for high accuracy mass flow measurement and can be configured to also output density information based on the resonant frequency of the vibrating flow tubes. Ultrasonic transducer Ultrasonic waves are passed from a source, through the fluid of interest, and into a detector which measures the acoustic spectroscopy of the waves.

Fluid properties such as density and viscosity can be inferred from the spectrum.