Density of a substance

What is the minimum density of a substance necessary to keep the buoyancy correction to less than 0.01% when using brass calibration weights with a density of 8.40 g/cm ... 

Density is defined as the mass of a substance contained in a unit volume. In the SI system of units, the ratio of the density of a substance to the density of water at I5°C is known as its relative density, while the older term specific gravity is the ratio relative to water at 60°F. Various units of density, such as kg/m, Ib-mass/fF, and g/cm, are commonly used. In addition, molar densities, or the density divided by the molecular weight, is often specified. This section briefly discusses methods of correlation of density as a function of temperature and presents the most common accurate methods for prediction of vapor, liquid, and solid density. 

Tlie specific gra ity (SG) is the ratio of tlie density of a substance to tlic density of a reference substance at a specific condition. 

The density of a substance is its weight per unit of volume. The unit of volume in the English system of measurement is 1 cubic foot or 1 f. To find the density of a substance, you must know its weight and volume. You then divide its weight by its volume to find the weight per unit volume. 

Ratio of the density of a substance to that of water. Spheroidization ... 

The density of a substance is independent of the size of the sample because doubling the volume also doubles the mass so the ratio of mass to volume remains the same. Density is therefore an intensive property. We distinguish different substances by their intensive properties. Thus, we might recognize a sample as water by noting its color, density (1.00 g-cm-3), melting point (0°C), boiling point (100°C), and the fact that it is a liquid. 

It is necessary to use the proper units when calculating the density of a substance. Densities of liquids and solids are usually expressed in terms of g/mL or g/cm3. Densities of gases are usually expressed in g/L. 

The mass density of a substance is an intensive quantity defined by ... 

The density of a material is a function of temperature and pressure but its value at some standard condition (for example, 293.15 K or 298.15 K at either atmospheric pressure or at the vapor pressure of the compound) often is used to characterize a compound and to ascertain its purity. Accurate density measurements as a function of temperature are important for custody transfer of materials when the volume of the material transferred at a specific temperature is known but contracts specify the mass of material transferred. Engineering applications utilize the density of a substance widely, frequently for the efficient design and safe operation of chemical plants and equipment. The density and the vapor pressure are the most often-quoted properties of a substance, and the properties most often required for prediction of other properties of the substance. In this volume, we do not report the density of gases, but rather the densities of solids as a function of temperature at atmospheric pressure and the densities of liquids either at atmospheric pressure or along the saturation line up to the critical temperature. 

Density is also dependent on temperature and tabulated values of density are valid only at the specified temperature. A related but more versatile is the specific gravity. This is the ratio of the density of a substance to the density of water at the same temperature. 

The density of a substance may be obtained simply by measuring its mass and volume and making the necessary calculation. The units for mass are typically given in grams, while the units for volume may be milhhters (cubic centimeters) or liters, depending on the physical state of the substance. The volume of solids and liquids is given in cubic centimeters or milliliters. 

The volume of a substance changes with the temperature, thus affecting its density. When determining the density of a substance, the temperature should also be measured and recorded. It is generally reported along with the density value in one of the following formats ... 

Closely related to density is specific gravity. Specific gravity compares the density of a substance to the density of a reference substance. Typically, for solids and liquids, this reference substance is water at 4°C,... 

Density is the mass of a material per unit volume, which is the ratio of the density of a substance to that of some standard, notably water. Water has a density of about 1 g/cm3, whereas carbon tetrachloride (CC14), an important DNAPL contaminant, has a density of about 1.58 g/cm3 and will tend to sink through the water table. 

The density of a substance is commonly calculated in chemistry. The density (D) of an object is calculated by dividing the mass of the object by its volume. (Some authors will use a lowercase d to represent the density term be prepared for either.) Since density is independent of the quantity of matter (a big piece of gold and a little piece have the same density), it can be used for identification purposes. The most common units for density in chemistry are g/cm3 or g/mL. 

The degree of compactness can be expressed as the density of a substance, which is defined as... 

Vapor density The vapor density of a substance is defined as the ratio of the mass of vapor per unit volume. An equation for estimating vapor density is readily derived from a varied form of the ideal gas law ... 

The specific vapor density of a substance relative to air is determined using ... 

A physicist measures the density of a substance to be 20 kg/m. His chemist colleague, appalled with the excessively large units, decides to change the units of the measurement to the more familiar grams per cubic centimeter. What is the new expression of the density ... 

Find the molarity and molality of 37.0 wt% HC1. The density of a substance is the mass per unit volume. The table inside the back cover of this book tells us that the density of the reagent is 1.19 g/mL. 

CRITICAL DENSITY. The density of a substance which is at its critical temperature and critical pressure. 

DENSITY. The density of a substance is its mass per unit volume, usually expressed in grams per cubic centimeter. The specific gravity of the substance is the ratio of its density to that of water, usually at 4°C, or 20°C, or 60°F, in the same units, and is therefore an abstract number independent of units. The density of a body is the ratio of its mass to its volume. 

Figure 1-2 Schematic diagram of a Victor Meyer apparatus for determination of the vapor density of a substance that is volatile at the oven temperature 7V The air displaced from the heated chamber by the volatilization of the sample In the bulb is measured in the gas burette at temperature 72 as the difference in the burette readings V2 and V,.

Laws were found for the combustion of gases in laminar or turbulent flow. Similarity laws were formulated for flame propagation under conditions in which the difference in density of a substance before and after combustion causes convective motion of the gas and flame.1... 

Knowing the density of a substance, particularly a liquid, can be very useful because it s often easier to measure a liquid by volume than by mass. Suppose, for example, that you needed 1.55 g of ethyl alcohol. Rather than trying to weigh exactly the right amount, it would be much easier to look up the density of ethyl alcohol (0.7893 g/mL at 20°C) and measure the correct volume with a syringe. 

To understand the significance of material properties, one only has to think of density, which is also a material property. The density of a substance defines how much volume, let s say, of water, that the substance will displace on immersion. Instead of measuring the volume of water each time one drops this substance in any container of water, one measures its density and calculates how much water it will displace on immersion. Clearly, the material property concept leads to predictive abilities. It is now known that the relative ordering of the molecules in a simple bodymatter defines its density and that by altering the ordering of the molecules, one... 

The unit is represented according to the international system of units (SI system). It is however often deviated from. In chemistry the units g / 1 and g / ml are often used. All substances, whether solid, liquid or gaseous and pure or impure have a certain density. The numerical value of this density indicates how much mass classifies under a certain volume and is dependent on the temperature. When a certain mass is heated, the substance will expand whereas the mass remains the same, the volume increases and consequently the density decreases. The density of a substance can be minute, e.g. 0.000082 g / ml for... 

The density of a substance is the weight per unit volume of the substance. Density of a substance is also known as its specific gravity. The density of water is 1. It is used as the standard to find out the density of other substances. The density of sea water is 1.025. 

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