Mass deficiency

The term mass deficiency better describes the fact that the exact mass of an isotope or a complete molecule is lower than the corresponding nominal mass. In case of for example, the isotopic mass is 15.994915 u, being 5.085 mmu deficient as compared to the nominal value. 

Fig. 3.22. Partial high-resolution El mass spectmm in the molecular ion region of a zirconium complex. Ai R = 8000 the PFK ion can barely be separated from the sUghtly more mass deficient analyte ion. By courtesy of M. Enders, University of Heidelberg.

Figure 4.14. Variety of metabolites for ketotifen, verapamil, indinavir, and para-acetoaminophe-nol including cleavages which take place giving a maximum mass deficiency of 167.7 mDa away from the parent compound. Mass deficiency shifts are very specific for each metabolite and parent drug.

The energy equivalent (E = mcA2) of the mass deficiency of an atom, where E = is the energy in joules, m is the mass in kilograms, and c is the speed of light in m/sA2 Boiling Point... 

For a reversible reaction, aA + bB cC + dD the product of the concentrations of the products (species on the right), each raised to the power that corresponds to its coefficient in the balanced chemical equation, divided by the product of the concentrations of reactants (species on the left), each raised to the power that corresponds to its coefficient in the balanced chemical equation. At equilibrium the mass action expression is equal to K at other times it is Q.[C]c[D]d [A]a[B]b = Q, or at equilibrium K Mass Deficiency... 

Energy equivalent of the mass deficiency energy released in the formation of an atom from the subatomic particles. 

Describe the relationships between neutron-proton ratio and nuclear stability Tell what is meant by the band of stability Calculate mass deficiency and nuclear binding energy... 

Experimentally, we observe that the masses of atoms other than H are always less than the sum of the masses of their constituent particles. We now know why this mass deficiency occurs. We also know that the mass deficiency is in the nucleus of the atom and has nothing to do with the electrons however, because tables of masses of isotopes include the electrons, we shall also include them. 

The mass deficiency, Aw, for a nucleus is the difference between the sum of the masses of electrons, protons, and neutrons in the atom (calculated mass) and the actual measured mass of the atom. 

For most naturally occurring isotopes, the mass deficiency is only about 0.15% or less of the calculated mass of an atom. 

Calculate the mass deficiency for chlorine-35 atoms in amu/atom and in g/mol atoms. The actual mass of a chlorine-35 atom is 34.9689 amu. 

We first find the numbers of protons, electrons, and neutrons in one atom. Then we determine the calculated mass as the sum of the masses of these particles. The mass deficiency is the actual mass subtracted from the calculated mass. This deficiency is commonly expressed either as mass per atom or as mass per mole of atoms. 

We have calculated the mass deficiency in amu/atom. Recall (Section 5-9) that 1 gram is 6.022 X 10 amu. We can show that a number expressed in amu/atom is equal to the same number in g/mol of atoms. 

A mass deficiency represents the amount of matter that would be converted into energy and released if the nucleus were formed from initially separate protons and neutrons. This energy is the nuclear binding energy, BE. It provides the powerful short-range force that holds the nuclear particles (protons and neutrons) together in a very small volume. 

The mass deficiency that we calculated in Example 26-1 is related to the binding energy by the Einstein equation. 

Binding energy (nuclear binding energy) The energy equivalent (E = mfi) of the mass deficiency of an atom. 

Mass deficiency The amount of matter that would be converted into energy if an atom were formed from constituent particles. 

What is mass deficiency What is binding energy How are the two related ... 

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