Ethanol mass percent

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. 

Another application of ICP-MS in the area of food safety is the evaluation of food contact materials. Q [86] and TOF [87] mass spectrometers have been employed in the compositional analysis of paper and board material intended for food contact. Studies on the migration of metals from food contact plastics using food simulants and ICP-MS detection have also been reported. One of them showed how to analyze different simulants without the need of any time-consuming preparation, that is, aqueous acetic acid (3 percent w/v) directly, aqueous ethanol (15 percent v/v) after proper dilution, the olive oil simulant following emulsion preparation by means of tetralin and Triton X-100 [88]. 

The mass percent (often called the weight percent) of carbon in ethanol can be computed by comparing the mass of carbon in 1 mole of ethanol with the total mass of 1 mole of ethanol and multiplying the result by 100% ... 

The mass percents of hydrogen and oxygen in ethanol are obtained in a similar manner ... 

A bottle of wine contains 12.5% ethanol by volume. The density of ethanol (C2H5OH) is 0.789 g/cm3. Calculate the concentration of ethanol in wine in terms of mass percent and molality. 

In a solution of acetone (CH3COCH3) and ethanol (C2H5OH), the mole fraction of acetone is 0.40. What is the concentration of acetone in terms of mass percent ... 

FOLLOW-UP PROBLEM 13.4 An alcohol solution contains 35.0 g of 1-propanol (C3H7OH) and 150. g of ethanol (C2H5OH). Calculate the mass percent and the mole fraction of each alcohol. 

The composition dependence of the surface tension of binary mixtures of severed compounds with water is given in this table. The data are tabulated as a function of the mass percent of the non-aqueous component. Data for methanol, ethanol, 1-propanol, and 2-propanol are taken from Reference 1, which also gives values at other temperatures. 

A solution is prepared by mixing 1.00 g of ethanol, C2H5OH, with 100.0 g of water. Calculate the mass percent of ethanol in this solution. 

Now, we need to turn to converting the concentrations into appropriate units. Since the total flowrates are given in terms of mass, a unit that expresses the concentration in terms of mass of the components would be most useful. The vapor stream compositions are given as mass percents, which works well with the units of flow. However, the liquid phase concentration given in terms of a molarity is not useful for finding a mass flow rate of ethanol (or of water). Hence we must convert the concentration to something more useful. 

We want to determine the mass percent of a given ethanol solution. 

In this case we have 1.00 g of solute (ethanol) and 100.0 g of solvent (water). We now apply the definition of mass percent. 

A solution is made containing 20.8 g phenol (CgHsOH) in 425 g ethanol (C2H5OH). Calculate (a) the mole fraction of phenol, (b) the mass percent of phenol, (c) the molality of phenoL... 

Calculate the mass percent of a solution containing 27.5 g of ethanol (C2H6O) and 175 mL of H2O. (Assume that the density of water is 1.00 g/mL.)... 

Begin by setting up the problem. You are given the mass of ethanol and the volume of water and asked to find the mass percent of the solution. 

To find the mass percent, substitute into the equation for mass percent. You need the mass of ethanol and the mass of water. Obtain the mass of water from the volume of water by using the density as a conversion factor. 

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