Water gram molecular mass

Water soluble protein with a relative molecular mass of ca. 32600, which particularly contains copper and zinc bound like chelate (ca. 4 gram atoms) and has superoxide-dismutase-activity. It is isolated from bovine liver or from hemolyzed, plasma free erythrocytes obtained from bovine blood. Purification by manyfold fractionated precipitation and solvolyse methods and definitive separation of the residual foreign proteins by denaturizing heating of the orgotein concentrate in buffer solution to ca. 65-70 C and gel filtration and/or dialysis. 

From (2), the solution contains 0.2mol dnC3 NaCl, or 11.7g dm-3. If the density is 1.006, then 1dm3 has a mass of 1006 g. 1dm3, therefore, contains 1006 — 11.7 g of water, or 994.3 g. Since the gram molecular weight of water is 18 g, this indicates that there are ... 

Here R is in the cgs (cm-gram-second) unit of 8.31 x 107 erg mol-1 deg-1. Using this equation the relative molecular mass Mr, which is numerically the same as M, can be evaluated from the sedimentation constant s. Since s, D, and v must all be measured with care, the method is demanding. It is often necessary to measure s and D at several concentrations and to extrapolate to infinite dilution. It is also customary to correct the data to give the values s°20 w and D°20 w expected at 20°C in pure water at infinite dilution. 

Relative atomic masses have no units because they are ratios of two masses measured in whatever units we choose (grams, kilograms, pounds, and so forth). The relative molecular mass of a compound is the sum of the relative atomic masses of the elements that constitute it, each one multiplied by the number of atoms of that element in a molecule. For example, the formula of water is H2O, so its relative molecular mass is... 

The mass (in grams) of Na atoms of any element is numerically equal to the relative atomic mass of that element. The same conclusion applies to molecules. From the relative molecular mass of water calculated earlier, the mass of Na molecules of water is 18.0152 g. 

From the molecular mass we can determine the molar mass of a molecule or compound. The molar mass of a compound (in grams) is numerically equal to its molecular mass (in amu). For example, the molecular mass of water is 18.02 amu, so its molar mass is 18.02 g. Note that 1 mole of water weighs 18.02 g and contains 6.022 X 10 H2O molecules, just as 1 mole of elemental carbon contains 6.022 X 10 carbon atoms. 

A mole is the mass of a substance in grams that corresponds to its molecular mass, expressed in grams. Thus, a mole of water (H2O) has a mass of 18 g (2H = 2, 10 = 16, total molecular mass = 16 + 2 = 18). This mole may also be called a gram-mole for clarity. 

One gram-molecular weight (abbreviation mole or mol) of any compound is a mass of that compound equal to its molecular weight in grams. Thus, 1 mole of water is 18.015 g of water. One mole of any compound contains the same number of molecules as one mole of any other compound. The number of molecules in 1 mole of any compound is 6.022 X 10 which is called Avogadro s number (A /v) Since the volume occupied by a gas depends on its temperature, pressure, and the number of molecules in the gas, at the same temperature and pressure 1 mole of the gas of any compound occupies the same volume as 1 mole of the gas of any other compound. At standard temperature and pressure (STP), which are defined as 0°C and 1 bar (=10 Pa), the volume occupied by 1 mole of any gas is about 22.4 L. 

The freezing point of water is 0.00°C at 1 atmosphere. Kj for water is 1.86°C/m. In a laboratory experiment, students synthesized a new compound and found that when 11.2 grams of the compound were dissolved in 2.80 X 10 grams of water, the solution began to freeze at —1.12°C. The compound was also found to be a nonvolatile molecular compound. What is the molecular mass that they determined for this compound ... 

So, for example, a mol of water (H2O) is 6.023 x 10 molecules of water. The molecular weight of water is M = 18g/mol so that the mass of a mol of water is 18 g. (A better name for this quantity would be the molecular mass, because the gram is a unit of mass. But molecular weight is the common name.)... 

C04-0009. Combustion reactions require molecular oxygen. In an automobile the fuel-injection system must be adjusted to provide the right mix of gasoline and air. Compute the number of grams of oxygen required to react completely with 1.00 L of octane (CgHig,p = 0.80 g/mL). What masses of water and carbon dioxide are produced in this reaction ... 

A gram-mole or mol of a compound is the molecular weight of the compound in grams for example, 1 mol H2O has a mass of 18.01 grams. A pound-mole or lb-mole is the molecular weight in pounds mass for example, 1 Ib-mole H2O has a mass of 18.01 Ibm. The molecular weight of water may therefore be expressed as 18.01 g/mol, 18.01 Ib /lb-mole. and so on, and it may be used to convert masses to moles or mass flow rates to molar flow rates and vice versa. 

Molarity it is only useful when the compositions of the constituents in water are known, since to evaluate molarity requires dividing the mass of each constituent in grams (per liter of solution) by the respective molecular weights. This system is, therefore, more complicated to evaluate but the results can be... 

---