Conversion factor mole

We now want to use this equivalence statement to obtain the conversion factor (mole ratio) that we need. Because we want to go from moles of H2O to moles of O2, we need the mole ratio... 

Use units as a check to see that you have used the correct conversion factors (mole ratios). 

The appropriate conversion factor (moles of CgHg must cancel) is 3 mol CO2/I mol CgHg, and the calculation is... 

Chemical Formulas as Conversion Factors (Moles to Moles)... 

Exact numbers, such as the stoichiometric coefficients in a chemical formula or reaction, and unit conversion factors, have an infinite number of significant figures. A mole of CaCb, for example, contains exactly two moles of chloride and one mole of calcium. In the equality... 

Table 47. Constants and Conversion Factors Avogadro s number = 6.023 X 10s per mole Electronic charge = 4.802 X 10-10 e.s.u.

Strategy To go from concentration of solute to concentration of an individual ion, you must know the conversion factor relating moles of ions to moles of solute. To find this conversion factor, it is helpful to write the equation for the solution process. 

Strategy (1) Start by calculating the number of moles of Fe2+. Then (2) use the coefficients of the balanced equation to find the number of moles of Mn04. Finally, (3), use molarity as a conversion factor to find the volume of KMn04 solution. 

As pointed out in Chapter 3, a balanced equation can be used to relate moles or grams of substances taking part in a reaction. Where gases are involved, these relations can be ex tended to include volumes. To do this, we use the ideal gas law and the conversion factor approach described in Chapter 3. 

A chemical equation tells us the relations between the amounts (in moles) of each reactant and product. By using the molar masses as conversion factors, we can express these relations in terms of masses. 

Molar mass can be thought of as a conversion factor between mass in grams and number of moles. These conversions are essential in chemistry, because chemists count amounts of substances in moles but routinely... 

Avogadro s number is the conversion factor that iinks the number of moles with the number of individual particles. To determine the number of atoms in a sample of an element, we multiply the number of moles by Avogadro s number — n Likewise, if a sample contains a certain number of atoms, the number of moles in the sample... 

Ans. There are 6.02 X 10 i atoms in 1.00 mol Na (Avogadro s number). There is 23.0 g of Na in LOO mol Na (equal to the atomic weight in grams). This problem requires use of two of the most important conversion factors involving moles. Note which one is used with masses and which one is used with numbers of atoms (or molecules of formula units). With numbers of atoms, molecules, or formula units, use Avogadro s number with mass or weight use the formula weight. 

It is possible to use such a conversion factor, but it is advisable while you are learning to use the factors involved with moles to use as few different ones as possible. That way, you have to remember fewer. Also, in each conversion you will change either the unit (mass - moles) or the chemical (CaCO, - O atoms) in a factor, but not both. Many texts do use such combined factors, however. 

Fig. 8-1 The conversion of moles of one reagent to moles of another, using a ratio of the coefficients of the balanced chemical equation as a factor label...

The pivotal conversion is from one substance to another, in moles with the balanced chemical equation providing the conversion factor. 

Avogadro s number is the conversion factor used to move between particle counts and numbers of moles. Notice that mole is abbreviated as mol. 

The most common particles that you use with the mole are atoms and molecules. When encountering a problem that deals with a specific unit, like molecules, you just replace particles with the correct unit, as in the following example. Like all conversion factors, you can invert this fraction to move in the other direction, from moles to particles. (Flip to Chapter 2 for an introduction to conversion factors.)... 

X10 molecules. To convert from moles to particles, use a conversion factor with moles in the denominator and particles in the numerator ... 

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