Examples of mass defect in the following topics:
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- A nucleus weighs less than its sum of nucleons, a quantity known as the mass defect, caused by release of energy when the nucleus formed.
- This mass, known as the mass defect, is missing in the resulting nucleus and represents the energy released when the nucleus is formed.
- Once mass defect is known, nuclear binding energy can be calculated by converting that mass to energy by using E=mc2.
- First, you must calculate the mass defect.
- Calculate the mass defect and nuclear binding energy of an atom
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- To balance a nuclear equation, the mass number and atomic numbers of all particles on either side of the arrow must be equal.
- Nuclear reactions may be shown in a form similar to chemical equations, for which invariant mass, which is the mass not considering the mass defect, must balance for each side of the equation.
- To balance the equation above for mass, charge, and mass number, the second nucleus on the right side must have atomic number 2 and mass number 4; it is therefore also helium-4.
- The result is an atomic mass difference of 4 and an atomic number difference of 2.
- In order to solve this equation, we simply add the mass numbers, 214 for polonium, plus 8 (two times four) for helium (two alpha particles), plus zero for the electrons, to give a mass number of 222.
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- Ionizing radiation from fallout can cause genetic effects, birth defects, cancer, cataracts, and other organ and tissue defects.
- Ionizing radiation from fallout can cause genetic effects, birth defects, cancer, cataracts, and other organ and tissue defects.
- Recognize the name of the genetic defect that has been shown to be caused by acute radiation exposure during pregnancy
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- The molar mass of a particular substance is the mass of one mole of that substance.
- The mass of one mole of atoms of a pure element in grams is equivalent to the atomic mass of that element in atomic mass units (amu) or in grams per mole (g/mol).
- Molar mass is the mass of a given substance divided by the amount of that substance, measured in g/mol.
- The characteristic molar mass of an element is simply the atomic mass in g/mol.
- However, molar mass can also be calculated by multiplying the atomic mass in amu by the molar mass constant (1 g/mol).
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- The law of conservation of mass states that mass in an isolated system is neither created nor destroyed.
- However, Antoine Lavoisier described the law of conservation of mass (or the principle of mass/matter conservation) as a fundamental principle of physics in 1789.
- In other words, in a chemical reaction, the mass of the products will always be equal to the mass of the reactants.
- This law was later amended by Einstein in the law of conservation of mass-energy, which describes the fact that the total mass and energy in a system remain constant.
- However, the law of conservation of mass remains a useful concept in chemistry, since the energy produced or consumed in a typical chemical reaction accounts for a minute amount of mass.
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- The average atomic mass of an element is the sum of the masses of its isotopes, each multiplied by its natural abundance.
- These different types of helium atoms have different masses (3 or 4 atomic mass units), and they are called isotopes.
- Then, calculate the mass numbers.
- To calculate the average atomic mass, multiply the fraction by the mass number for each isotope, then add them together.
- Whenever we do mass calculations involving elements or compounds (combinations of elements), we always use average atomic masses.
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- In assigning mass values to atoms and molecules, we have assumed integral values for isotopic masses.
- Thus, relative to 12C at 12.0000, the isotopic mass of 16O is 15.9949 amu (not 16) and 14N is 14.0031 amu (not 14).
- By designing mass spectrometers that can determine m/z values accurately to four decimal places, it is possible to distinguish different formulas having the same nominal mass.
- Mass spectrometry therefore not only provides a specific molecular mass value, but it may also establish the molecular formula of an unknown compound.
- Tables of precise mass values for any molecule or ion are available in libraries; however, the mass calculator provided below serves the same purpose.
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- Mass-to-mole conversions can be facilitated by employing the molar mass as a conversion ratio.
- The relative atomic mass is a ratio between the average mass of an element and 1/12 of the mass of an atom of carbon-12.
- From the relative atomic mass of each element, it is possible to determine each element's molar mass by multiplying the molar mass constant (1 g/mol) by the atomic weight of that particular element.
- The molar mass value can be used as a conversion factor to facilitate mass-to-mole and mole-to-mass conversions.
- The molar mass of water is 18 g/mol.
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- Mass-to-mass conversions cannot be done directly; instead, mole values must serve as intermediaries in these conversions.
- It is not possible to directly convert from the mass of one element to the mass of another.
- Therefore, for a mass-to-mass conversion, it is necessary to first convert one amount to moles, then use the conversion factor to find moles of the other substance, and then convert the molar value of interest back to mass.
- Because there is no direct way to compare the mass of butane to the mass of oxygen, the mass of butane must be converted to moles of butane:
- A chart detailing the steps that need to be taken to convert from the mass of substance A to the mass of substance B.
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- Mass spectrometry is a powerful characterization method that identifies elements, isotopes, and compounds based on mass-to-charge ratios.
- Mass spectrometers separate compounds based on a property known as the mass-to-charge ratio: the mass of the atom divided by its charge.
- A mass analyzer, which sorts the ions by mass by applying electromagnetic fields
- Mass analyzers separate the ions according to their mass-to-charge ratios.
- There are many types of mass analyzers.