SI Units What is the relationship between the SI unit for volume and the SI unit for length [Pg.62]

As shown above, the SI unit for volume is the cubic meter (m3), but most chemists use the liter (L, which is equal to 1 cubic decimeter (dm3)) or milliliter (mL). Appendix A lists the SI base units and prefixes, as well as some English-SI equivalents. [Pg.44]

In fact, the derived SI unit for volume is the cubic meter. It is easy to visualize a cubic meter imagine a large cube whose sides are each 1 m in length. The volume of an irregularly shaped solid can be determined using the water displacement method, a method used in the MiniLab in this section. [Pg.35]

The SI units for reaction rate are moles per cubic meter per second, but other time units are frequently used and other volume units are sometimes used. It is obviously necessary to specify to what compound the reaction rate refers. This book makes the specification essentially automatic by defining a rate, 01, for the reaction as a whole. The reaction rate for component A is denoted 01k and is found from [Pg.5]

As shown in the above example, the SI unit for volume is litres (1) and density is grams per litre (gl ). For further details on SI units and common prefixes, please see Appendix 1. [Pg.37]

Let s discuss some of the SI units for quantities that we use early in the text length, volume, mass, density, temperature, and time. (Units for other quantities are presented in later chapters, as they are used.) Table 1.3 shows some useful SI quantities for length, volume, and mass, along with their equivalents in the English system. [Pg.14]

Note An equivalent SI unit for the liter is dm. Rate constants and Arrhenius pre-exponential factors incorporating volume units are sometimes reported using dm or cm instead of liters. Those incorporating amount units are sometimes reported in units of molecules instead of moles. For example, a second-order rate constant of 1.2 x lO" L-moP -s" is equivalent to 1.2 X lO" dm -moP -s" or 2.0 x 10" ° cm molecule" -s". [Pg.165]

The SI unit for concentration is moles per cubic meter (mol/m3). Mole (mol) is the base SI unit for the amount of substance. Cubic meter (m3) is a derived unit for volume. The use of regularly formed multiples such as cubic centimeter and cubic decimeter is also allowed. The special name liter (51) has been approved for use instead of cubic decimeter, but its use is restricted to the measurement of liquids and gases. [Pg.185]

Specific volume is commonly used in the study of thermodynamics. The SI unit for specific volume is m /kg. Another common way to represent the heaviness or lightness of some material is by comparing its density to the density of water. This comparison is called the spee gravity of a material and is formally defined by [Pg.222]

The SI unit for heat capacity is J-K k Molar heat capacities (Cm) are expressed as the ratio of heat supplied per unit amount of substance resulting in a change in temperature and have SI units of J-K -moC (at either constant volume or pressure). Specific heat capacities (Cy or Cp) are expressed as the ratio of heat supplied per unit mass resulting in a change in temperature (at constant volume or pressure, respectively) and have SI units of J-K -kg . Debye s theory of specific heat capacities applies quantum theory in the evaluation of certain heat capacities. [Pg.333]

Hie concentration unit consistent with the conventional SI units for R is mol m-3. In that regard, the derivation of the Van t Hoff relation (Eq. 2.10) uses the volume of water, not the volume of the solution, so technically a unit based on molality is implied. However, the Van t Hoff relation is only an approximate representation of the osmotic pressure appropriate for dilute solutions, for which the numerical difference between molality and molarity is usually minor, as indicated in the text. Thus, molarity of osmotically active particles (= osmolarity) is suitable for most calculations and is generally more convenient (note that concentration in moles per m3 is numerically equal to ihm). [Pg.69]

I have deliberately violated this rule in using two different symbols for the volume concentration. The traditional symbol for the volume concentration in units of mol per litre is c. This is a non-SI unit in the sense that it is not derived directly from the base units, but involves a numerical factor as well. It is an SI unit in the sense that it involves legitimate SI units for amount of substance (mol) and volume (dm ). As a laboratory unit of concentration c is going to be with us for a long time. Rather than use this symbol for the SI unit of concentration derived simply from the base units, mol/m, I have introduced the symbol c for the SI base unit concentration. The use of c in the equations avoids both cumbersome numerical factors and confusion with the moles-per-litre concentration. Similarly, I have used A for number of molecules per cubic metre. [Pg.965]

The polarizability a, like the permanent dipole moment /x, is an intrinsic property of a molecule. SI units for a are C m but values are usually reported for the quantity a = a/4,7T (], in cm. The volumetricunitsfor a suggest apossiblecoimectionbetween polarizability and molecular volume. Typically, a increases with molecular volume very rouglily, a 0.05 cr, where a is tire molecular collision diameter. Hence a normally falls in tire rarrge of about 1 to 25 X 10 " cirr. [Pg.605]

Not all quantities can be measured with SI base units. For example, the SI unit for speed is meters per second (m/s). Notice that meters per second includes two SI base units—the meter and the second. A unit that is defined by a combination of base units is called a derived unit. Two other quantities that are measured in derived units are volume (cm ) and density (g/cm ). [Pg.35]

A measurement is a quantitative observation involving both a number and a unit. What is a qualitative observation What are the SI units for mass, length, and volume What is the assumed uncertainty in a number (unless stated otherwise) The uncertainty of a measurement depends on the precision of the measuring device. Explain. [Pg.32]

When making calculations, we will generally convert all data to their values in SI units, since calculations involving SI units give answers in SI units. For example, when calculating the volume of an ideal gas from the equation [Pg.34]

If the pressure F xt is expressed in pascals and the volume in cubic meters, their product is in joules (J). These are the International System of Units (SI) units for [Pg.492]

The SI base units are used to obtain derived units. To do so, we use the defining equation for the quantity, substituting the appropriate base units. For example, speed is defined as the ratio of distance traveled to elapsed time. Thus, the SI unit for speed—m/s, read meters per second —is a derived unit, the SI unit for distance (length), m, divided by the SI unit for time, s. Two common derived units in chemistry are those for volume and density. [Pg.18]

A gas is a collection of atoms or molecules moving independently through a volume that is largely empty space. Collisions of the randomly moving particles with the walls of their container exert a force per unit area that we perceive as pressure. The SI unit for pressure is the pascal, but the atmosphere and the millimeter of mercury are more commonly used. The physical condition of any gas is defined by four variables pressure (P), temperature (T), volume (V), and molar amount (n). The specific relationships among these variable are called the gas laws [Pg.370]

R is obtained in joules per kelvin per mole R = 8.314 J-K-1-mol" Table 4.2 lists the values of R in a variety of different units which are useful if volume or pressure is reported in other than SI units. For instance, it is sometimes convenient to use R in liter-atmospheres per kelvin per mole R = 8.206 X 10 "2 L-atnvk -mol [Pg.270]

The international scientific community prefers to work exclusively with a single set of units, the Systeme International (SI), which expresses each fundamental physical quantity in decimally (power of 10) related units. The seven base units of the SI are listed in Table 1-3. The SI unit for volume is obtained from the base unit for length A cube that measures 1 meter on a side has a volume of 1 cubic meter. [Pg.31]

Various units are used for expressing pressures (see Chapter 1, Footnote 8). A pressure of one standard atmosphere, or 0.1013 MPa, can support a column of mercury 760 mm high or a column of water 10.35 m high. As indicated in Chapter 1, the SI unit for pressure is the pascal (Pa), which is 1 N m-2 an SI quantity of convenient size for hydrostatic pressures in plants is often the MPa (1 MPa = 10 bar = 9.87 atm). (An extensive list of conversion factors for pressure units is given in Appendix II, which also includes values for related quantities such as RT.) Pressure is force per unit area and so is dimensionally the same as energy per unit volume (e.g., 1 Pa = 1 N m-2 = 1J m-3). Vw has the units of m3 mol-1, so VWP and hence /aw can be expressed in J mol-1. [Pg.64]

Molality, symbolized by m and usually followed by a subscript denoting the component, is also often used in physical biochemistry and is equal to the amount of substance per unit mass of solvent (eg., niB = hbI (wflxxsoivent))- The SI unit for molality, another temperature-independent quantity, is mol-kg k A quantity related to molality, yet not as widely used in physical studies, is the volume molality, symbolized by m . The volume molality is equal to the amount of substance per unit volume of solvent (recall that concentration was equal to amount of substance per unit volume of solution). [Pg.163]

Any system of measurement must decide what to do about the fact that there are literally thousands of physical properties that we measure, each of which is expressed as a measured number of some well-defined unit of measurement. It would be impossible to set up primary standards for the units of each and every one of these thousands of physical quantities, but fortunately there is no need to do so since there are many relationships connecting the measurable quantities to one another. A simple example that is of direct importance to the subject of this book is that of volume as mentioned above, the SI unit of volume (cubic meter) is simply related to the SI unit for length via the physical relationship between the two quantities. So the first question to be settled concerns how many, and which, physical quantities should be defined as SI base quantities (sometimes referred to as dimensions), for which the defined units of measurement can be combined appropriately to give the SI units for all other measurable quantities. [Pg.6]

See also in sourсe #XX -- [ Pg.17 ]

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