Search results
Results from the WOW.Com Content Network
Stoichiometry is not only used to balance chemical equations but also used in conversions, i.e., converting from grams to moles using molar mass as the conversion factor, or from grams to milliliters using density. For example, to find the amount of NaCl (sodium chloride) in 2.00 g, one would do the following:
Gives 1.1981 moles per scf or 0.002641 pound moles per scf. The standard cubic meter of gas (scm) is used in the context of the SI system. It is similarly defined as the quantity of gas contained in a cubic meter at a temperature of 15 °C (288.150 K; 59.000 °F) and a pressure of 101.325 kilopascals (1.0000 atm; 14.696 psi). [1]
The ideal gas equation can be rearranged to give an expression for the molar volume of an ideal gas: = = Hence, for a given temperature and pressure, the molar volume is the same for all ideal gases and is based on the gas constant: R = 8.314 462 618 153 24 m 3 ⋅Pa⋅K −1 ⋅mol −1, or about 8.205 736 608 095 96 × 10 −5 m 3 ⋅atm⋅K ...
where the pressure, p, is the atmospheric pressure, V is the measured volume of the vessel, T is the absolute temperature of the hot bath, and R is the gas constant. The molecular weight of the chemical is then simply the mass in grams of the vapor within the vessel divided by the calculated number of mole.
The lower heating value of natural gas is normally about 90% of its higher heating value. This table is in Standard cubic metres (1 atm , 15 °C), to convert to values per Normal cubic metre (1 atm, 0 °C), multiply above table by 1.0549.
Sometimes specific volume is expressed in terms of the number of cubic centimeters occupied by one gram of a substance. In this case, the unit is the centimeter cubed per gram (cm 3 /g or cm 3 ·g −1). To convert m 3 /kg to cm 3 /g, multiply by 1000; conversely, multiply by 0.001. Specific volume is inversely proportional to density.
Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...
For some usage examples, consider the conversion of 1 SCCM to kg/s of a gas of molecular weight , where is in kg/kmol. Furthermore, consider standard conditions of 101325 Pa and 273.15 K, and assume the gas is an ideal gas (i.e., Z n = 1 {\displaystyle Z_{n}=1} ).