Solutions mass percent

The concentration of a solution can be expressed in many ways, including molarity (moles of solute per liter of solution), mole fraction (moles of solute per mole of solution), mass percent (mass of solute per mass of solution times 100%), and molality (moles of solute per kilogram of solvent). When equilibrium is reached and no further solute dissolves in a given amount of solvent, a solution is said to be saturated. The concentration at this point represents the... 

Solution Concentration Solution concentration is useful in converting between amounts of solute and solution. Mass percent and molarity are the most common concentration units. Molality is used to quantify colligative properties such as freezing point depression and boiling point elevation. 

Mass Solute Mass Solvent Mass Solution Mass Percent Mass Solute Mass Solvent Mass Solution Mass Percent... 

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 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... 

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. 

The amount of sodium hypochlorite in a bleach solution can be determined by using a given volume of bleach to oxidize excess iodide ion to iodine CIO- is reduced to Cl-. The amount of iodine produced by the redox reaction is determined by titration with sodium thiosulfate, Na2S203 I2 is reduced to I-. The sodium thiosulfate is oxidized to sodium tetrathionate, Na2S406. In this analysis, potassium iodide was added in excess to 5.00 ml of bleach d = 1.00 g/cm3). If 25.00 mL of 0.0700 MNa2S203 was required to reduce all the iodine produced by the bleach back to iodide, what is the mass percent of NaCIO in the bleach ... 

C12-0035. A solution contains 1.521 g of maleic acid, HO2 CCHICHC02H, dissolved in 85.0 mL of acetone (p — 0.818 g/mL). Calculate the molality, mole fraction, and mass percent of maleic acid in the solution. 

Percentages can be used as factors. The percentage of something is the number of parts of that thing per hundred parts total. Whatever unit(s) is used for the item in question is also used for the total. For example, the percent by mass of water in a solution is the number of grams of water per hundred grams of solution or the number of kilograms of water per 100 kg of solution. The percent by volume of alcohol in a mixed drink is the number of milliliters of alcohol in lOOmL of the drink, and so forth. If the words by volume or some other similar words are not stated, assume percent by mass. 

A To determine mass percent, we need both the mass of ethanol and the mass of solution. From volume percent, we know that 100.0 mL of solution contains 20.0 mL pure ethanol. The density of pure ethanol is 0.789 g/mL. We now can determine the mass of solute (ethanol) and solution. We perform the calculation in one set-up. 

Since the pKA for H202 had been provided to us, we can find the solution pH simply by solving an I.C.E. table for the hydrolysis of a 3.0 % H202 solution (by mass). Of course, in order to use this method, the mass percent must first be converted to molarity. We must assume that the density of the solution is 1.0 g mL-1. 

Recap 50. mL samples of known concentration of[Ni(NH3)J2+ were made up by using NiS04 6 H20. The concentrations were then plotted versus their absorbance. The unknown solution s absorbance was then extrapolated from this graph and used in the calculation for the mass percent ofNi2+. 

One common way of expressing the relative amount of solute and solvent is through percentage, amount per hundred. There are three ways that we may express this percentage mass percent, mass/volume percent, and volume/volume percent. 

A solution is prepared by dissolving 45.2 g of sucrose in 250.0 g of water. Calculate the mass percent of the solution. 

A—To calculate the molarity, the moles of urea and the volume of the solution are needed. Density is an intensive property, so any arbitrary volume of solution may be used. One liter is a convenient volume. Using this volume and the density of the solution, you can calculate the mass of the solution. Ten percent of this is the mass of urea. The mass of urea and the molecular weight of urea give the moles of urea. 

Percent by Mass proportion of the mass of each element in a compound expressed as a percent or proportion of solute mass as total mass of solution Perfect Gas see Ideal Gas Period a horizontal row in the periodic table Permanent Hardness condition of water when magnesium and calcium are combined with chlorides and sulfates rather than carbonates, cannot be removed by heating Petrochemical chemicals derived from oil or natural gas... 

Percent solution is another common way to express concentration. The precise units of percent solution typically depend on the phase of each component. For solids dissolved in liquids, mass percent is usually used ... 

This kind of measurement is sometimes called a mass-mass percent solution because one mass is divided by another. Very dilute concentrations (as in the concentration of a contaminant in drinking water) are sometimes expressed as a special mass percent called parts per million (ppm) or parts per billion (ppb). In these metrics, the mass of the solute is divided by the total mass of the solution, and the resulting fraction is multiplied by 10 (ppm) or by 10 (ppb). 

Clearly, paying attention to units is important when working with concentration. Only by observing which units are attached to a measurement can you determine whether you re working with molarity, with mass percent, or with a mass-mass, mass-volume, or volume-volume percent solution. 

---