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Concentration percent by mass

Each concentration measure is convenient for some types of calculations but inconvenient for others. Consequently, a chemist may need to convert a concentration from one measure to another. Example illustrates the conversion from a mass-based concentration, percent by mass, to a mole-based concentration, molality. Mole... [Pg.832]

This chapter first considers the nature of the solution process (Section 15.1) and the quantity of solute that can dissolve in a given quantity of solvent (Section 15.2). Covered next are three temperature-independent measures of concentration— percent by mass (Section 15.3), molality (Section 15.4), and mole fraction (Section 15.5). Finally, colligative properties of solutions are considered in Section 15.6. [Pg.418]

Quantitative study of a solution requires knowing its concentration, that is, the amount of solute present in a given amount of solution. Chemists use several different concentration units, each of which has advantages as well as limitations. Let us examine the four most common units of concentration percent by mass, mole fraction, molarity, and molality. [Pg.471]

In Chapter 3, we discussed percent by mass as a concentration unit ... [Pg.194]

As discussed previously, military-grade TNT is not a pure material, containing additional nitroaromatic constituents at concentrations of up to several percent by mass [4], Some of these explosive-related compounds (ERCs) have been shown to be significant contributors to the chemical fingerprint of a landmine [5, 7], Of the ERCs found in TNT, those that are most prevalent in the headspace vapor of TNT include 2,4-DNT, 2,6-DNT, 1,3-dinitrobenzene (1,3-DNB), and... [Pg.159]

The amount of solute and solvent in a solution can be quantitatively expressed using numerous concentration units. The choice of a particular concentration unit depends largely on practice and convenience. We have probably all made solutions using recipes or directions that tell us to add so much water to a substance. In the field of chemistry, the most common concentration units are molarity, molality, percent by mass, and parts per. Each of these is defined here ... [Pg.129]

The density of vinegar is 1.01 g/mL. (The density of the more concentrated vinegar solution is greater than the density of the less concentrated solution. You can ignore the difference, however.) Calculate the mass of the vinegar sample. Find the percent by mass of acetic acid in the sample. [Pg.403]

To do calcnlations with percent by mass as a measnre of concentration... [Pg.417]

Percent by mass is a measure of concentration, defined as 100.0% times the mass of a component of the solution divided by the total mass of the solution. It is a temperature-independent concentration unit. It is often used for solutions in applied chemistry situations, such as medical laboratories and hospitals (Section 15.3). [Pg.437]

A mixture of methane and air is capable of being ignited only if the mole percent of methane is between 5% and 15%. A mixture containing 9.0 mo e% methane in air flowing at a rate of 700. kg/h is to be diluted with pure air to reduce the methane concentration to the lower flammability limit. Calculate the required flow rate of air in mol/h and the percent by mass of oxygen in the product gas. Note Air may be taken to consist of 21 mole% O2 and 79% N2 and to have an average molecular weight of 29.0.)... [Pg.69]

The surface of a mild steel component is commonly hardened by packing the component in a carbonaceous material in a furnace at a high temperature for a predetermined time. Consider such a component with a uniform initial carbon concentration of 0.15 percent by mass, The component is now packed in a carbonaceous material and is placed in a high-temperature furnace. The diffusion coefficient of carbon in steel at the furnace temperature is given to be 4.8 X 10" m /s, and the equilibrium concentration of carbon in the iron at the interface is determined from equilibrium data to be 1.2 percent by mass. Determine how long the component should be kept in the furnace for the I mass concentration of carbon 0.5 mm below the surface to reach 1 percent i (Fig. 14-28). p... [Pg.811]

Concentration expressed as a percent is a ratio of a measured amount of solute to a measured amount of solution. Percent by mass usually describes solutions in which a solid is dissolved in a liquid, such as sodium chloride in water. The percent by mass is the ratio of the solute s mass to the solution s mass expressed as a percent. The mass of the solution equals the sum of the masses of the solute and the solvent. [Pg.463]

In order to maintain a sodium chloride (NaCI) concentration similar to ocean water, an aquarium must contain 3.6 g NaCI per 100.0 g of water. What is the percent by mass of NaCI in the solution ... [Pg.463]

As you have learned, percent by volume and percent by mass are only two of the commonly used ways to quantitatively describe the concentrations of liquid solutions. One of the most common units of solution concentration is molarity. Molarity (M) is the number of moles of solute dissolved per hter of solution. Molarity also is known as molar concentration. The unit M is read as molar. A liter of solution containing one mole of solute is a IM solution, which is read as a one molar solution. A liter of solution containing 0.1 mole of solute is a 0.1 M solution. [Pg.464]

Which is more concentrated, 25 g NaCI dissolved in 500 ml of water or a 10% solution of NaCI (percent by mass) ... [Pg.880]

Concentrations of solutions may be expressed in terms of percent by mass of solute, which gives the mass of solute per 100 mass units of solution. The gram is the usual mass unit. [Pg.103]

We saw in Section 3-6 that concentrations of solutions are often expressed as percent by mass of solute or as molarity. Discussion of many physical properties of solutions is often made easier by expressing concentrations either in molality units or as mole fractions (Sections 14-9 to 14-14). [Pg.554]

The following terms were defined at the end of Chapter 3 concentration, dilution, molarity, percent by mass, solute, solution, and solvent. The following terms were defined at the end of Chapter 13 condensation, condensed phases, evaporation, phase diagram, and vapor pressure. [Pg.583]

Skill 16.4 Solving problems involving concentrations of solutions (e.g., molarity, molality, percent by mass percentage)... [Pg.188]

Another way of providing information about solution composition is to express how much solute is present relative to the maximum amount the solution could hold. If the amount of solute dissolved is less than the maximum that could be dissolved, the solution is called an unsaturated solution. The oceans of Earth are examples of imsaturated saltwater solutions. They could hold a higher concentration of salt than they do now. The maximum concentration of salt water is approximately 36 g of salt dissolved per every 100 g of water, or 36 percent by mass. Such a solution, which holds the maximum amount of solute per amoimt of the solution under the given conditions, is called a saturated solution. [Pg.458]

The concentration of a solution can be expressed as percent by mass, mole fraction, molarity, and molality. The choice of units depends on the circumstances. [Pg.497]

Concentrated hydrochloric acid is usually available at a concentration of 37.7 percent by mass. What is its molar concentration (The density of the solution is 1.19 g/mL.)... [Pg.502]

The concentration of commercially available concentrated sulfuric acid is 98.0 percent by mass, or 18 M. Calculate the density and the molality of the solution. [Pg.503]

FIGURE 19.9 Interior section of a lead storage battery. Under narmal aperating conditions, the concentration of the sulfuric acid solution is about 38 percent by mass. [Pg.777]

The concentration of sulfuric acid in the lead-storage battery of an automobile over a period of time has decreased from 38.0 percent by mass (density = 1.29 g/mL) to 26.0 percent by mass (1.19 g/mL). Assume the volume of the acid remains constant at 724 mL. (a) Calculate the total charge in coulombs supplied by the battery, (b) How long (in hours) will it take to recharge the battery back to the original sulfuric acid concentration using a current of 22.4 amperes. [Pg.798]

This reaction is accelerated by light, heat, or a catalyst. (a) Explain why hydrogen peroxide sold in drugstores comes in dark bottles, (b) The concentrations of aqueous hydrogen peroxide solutions are normally expressed as percent by mass. In the decomposition of hydrogen peroxide, how many liters of oxygen gas can be produced at STP from 15.0 g of a 7.50 percent hydrogen peroxide solution ... [Pg.867]

Although qualitative descriptions of concentration can be useful, solutions are more often described quantitatively. Some commonly used quantitative descriptions are percent by mass, percent by volume, molarity, and molality. These descriptions express concentration as a ratio of measured amounts of solute and solvent or solution. Table 14.3 lists each ratios description. [Pg.480]


See other pages where Concentration percent by mass is mentioned: [Pg.67]    [Pg.157]    [Pg.195]    [Pg.116]    [Pg.1024]    [Pg.493]    [Pg.851]    [Pg.116]    [Pg.841]   
See also in sourсe #XX -- [ Pg.170 ]




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