Mass percent

When a distribufion of particle sizes which must be collected is present, the aclual size distribution must be converted to a mass distribution by aerodynamic size. Frequently the distribution can be represented or approximated by a log-normal distribution (a straight line on a log-log plot of cumulative mass percent of particles versus diameter) wmich can be characterized by the mass median particle diameter dp5o and the standard statistical deviation of particles from the median [Pg.1428]

Figure 1 Thermal oxidative breakdown of polyethylene (temperature 200°C P02 = 350 Tor stabilizer concentration 0.5 mass percent). 1-without stabilizer 2-CaO-6 3-polydii-minodiphenylmethane disulfide 4-polydiiminodiphenylsul-fon disulfide 5-polyparaoxydiphenylamine disulfide 6-po-lydimethylaniline disulfide 7-polyaniline disulfide 8-polydiiminodiphenyloxide disulfide 9-polythiosemicarbaz-ide disulfide 10-polyamine disulfide 11-polycarbamide disulfide 12-poly thiocarbamide disulfide 13-polyethylenedi-amine disulfide.

Weight (or Mass) Basis. The terms weight fraction and weight percent" are often used as synonymous for mass fraction and mass percent, respectively. If the total... 

As you will see shortly, the formula of a compound can be used to determine the mass percents of the elements present. Conversely, if the percentages of the elements are known, the simplest formula can be determined. Knowing the molar mass of a molecular compound, it is possible to go one step further and find the molecular formula. In this section we will consider how these three types of calculations are carried out. 

The percent composition of a compound is specified by citing the mass percents of the elements present. For example, in a 100-g sample of water there are 11.19 g of hydrogen and 88.81 g of oxygen. Hence the percentages of the two elements are... 

Knowing the formula of a compound, Fe203> you can readily calculate the mass percents of its constituent elements. It is convenient to start with one mole of compound (Example 3.4a). The formula of a compound can also be used in a straightforward way to find the mass of an element in a known mass of the compound (Example 3.4b). 

Sometimes you will be given the mass percents of the elements in a compound. If that is the case, one extra step is involved. Assume a 100-g sample and calculate the mass of each dement in that sample. 

Turquoise has the following chemical formula CuAl (P04)4(0H)8 4H20. Calculate the mass percent of each element in turquoise. 

Hexachlorophene, a compound made up of atoms of carbon, hydrogen, chlorine, and oxygen, is an ingredient in germicidal soaps. Combustion of a 1.000-g sample yields 1.407 g of carbon dioxide, 0.134 g of water, and 0.523 g of chlorine gas. What are the mass percents of carbon, hydrogen, oxygen, and chlorine in hexachlorophene ... 

A certain hydrate of potassium aluminum sulfate (alum) has foe formula KA1(S04)2 - xH20. When a hydrate sample weighing 5.459 g is heated to remove all foe water, 2.583 g ofKAl(S04)2 remains. What is foe mass percent of water in foe hydrate What is x ... 

An artificial fruit beverage contains 12.0 g of tartaric acid, H2C4H406, to achieve tartness. It is titrated with a basic solution that has a density of 1.045 g/cm3 and contains 5.00 mass percent KOH. What volume of the basic solution is required (One mole of tartaric acid reacts with two moles of hydroxide ion.)... 

The chloride ion resulting from the reduction of HCIO is precipitated as AgCl. When 50.0 mL of laundry bleach (d = 1.02 g/cm3) is treated as described above, 4.95 g of AgCl is obtained. What is the mass percent of NaClO in tiie bleach ... 

It is found that 19.26 mL of 0.150 M NaOH is required to titrate the excess HC1 left after reaction with the limestone. What is the mass percent of CaC03 in the limestone ... 

Mass Percent Parts per Million Parts per Billion... 

The mass percent of solute in solution is expressed quite simply ... 

It is frequently necessary to convert from one concentration unit to another This problem arises, for example, in making up solutions of hydrochloric acid. Typically, the analysis or assay that appears on the label (Figure 10.2, p. 263) does not give the molarity or molality of the add. Instead, it lists the mass percent of solute and the density of the solution. 

Complex problems can usually be solved if Mass percent 100 g solution... 

The label on a bottle of concentrated hydrochloric acid. The label gives the mass percent of HCI in the solution (known as the assay] and the density (or specific gravity) of the solution. The molality, molarity, and mole fraction of HCI in the solution can be calculated from this information. 

Molality Mass Percent Ppm Solvent Solute Mole Fraction Solvent... 

Mass Percent Ppm Mole Fraction Molality Solvent Solute Solvent... 

Density (g/mL) Molarity Molality Mass Percent of Solute... 

Pure benzene boils at 80.10°C and has a boiling point constant, kb, of 2.53°CIm. A sample of benzene is contaminated by naphthalene, CioH8. The boiling point of the contaminated sample is 81.20°C. How pure is the sample (Express your answer as mass percent of benzene.)... 

The water-soluble nonelectrolyte X has a molar mass of 410 g/mol A 0.100-g mixture containing this substance and sugar (MM = 342 g/mol) is added to 1.00 g of water to give a solution whose freezing point is —0.500°C. Estimate the mass percent of X in the mixture. 

There are four iron atoms in each hemoglobin molecule. The mass percent of iron in a hemoglobin molecule is 0.35%. Estimate the molar mass of hemoglobin. 

This reaction is used to prepare high-purity phosphoric acid and salts of that acid for use in food products. Phosphoric acid, H O is added in small amounts to soft drinks to give them a tart taste. It is present to the extent of about 0.05 mass percent in colas, 0.01 mass percent in root beers. 

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