Examples of Beer's law in the following topics:
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- If we know the order of the reaction, we can plot the data and apply our integrated rate laws.
- The absorbance is given by Beer's law:
- By Beer's law, the absorbance of the solution is directly proportional to the concentration of the C60O3 in solution, so observing the absorbance as a function of time is essentially the same as observing the concentration as a function of time.
- In this case, the rate law is given by:
- As discussed in a previous concept, plots derived from the integrated rate laws for various reaction orders can be used to determine the rate constant k.
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- The equilibrium constant expression (Kc), according to the Law of Chemical Equilibrium, for this reaction is formulated as follows:
- The Beer-Lambert Law relates the amount of light being absorbed to the concentration of the substance absorbing the light and the path length through which the light passes:
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- The law of multiple proportions states that elements combine in small whole number ratios to form compounds.
- The law of multiple proportions, also known as Dalton's law, was proposed by the English chemist and meteorologist John Dalton in his 1804 work, A New System of Chemical Philosophy.
- The law, which was based on Dalton's observations of the reactions of atmospheric gases, states that when elements form compounds, the proportions of the elements in those chemical compounds can be expressed in small whole number ratios.
- Dalton's law of multiple proportions is part of the basis for modern atomic theory, along with Joseph Proust's law of definite composition (which states that compounds are formed by defined mass ratios of reacting elements) and the law of conservation of mass that was proposed by Antoine Lavoisier.
- These laws paved the way for our current understanding of atomic structure and composition, including concepts like molecular or chemical formulas.
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- The law of definite composition states that chemical compounds are composed of a fixed ratio of elements as determined by mass.
- In 1806, Proust summarized his observations in what is now called Proust's Law.
- There are some exceptions to the law of definite composition.
- In addition, the law of definite composition does not account for isotopic mixtures.
- This video examines the law of definite proportions and the law of multiple proportions.
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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.
- 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.
- An additional useful application of this law is the determination of the masses of gaseous reactants and products.
- A portrait of Antoine Lavoisier, the scientist credited with the discovery of the law of conservation of mass.
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- Step two is the slow, rate-determining step, so it might seem reasonable to assume that the rate law for this step should be the overall rate law for the reaction.
- The overall rate law cannot contain any such intermediates, because the rate law is determined by experiment only, and such intermediates are not observable.
- How to determine the rate law for a mechanism with a fast initial step.
- Remember, the overall rate law must be determined by experiment.
- Therefore, the rate law must contain no reaction intermediates.
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- Recall that the rate law for a first-order reaction is given by:
- Recall that the rate law for a second-order reaction is given by:
- The final version of this integrated rate law is given by:
- In this case, we can say that [A]=[B], and the rate law simplifies to:
- This is the standard form for second-order rate law, and the integrated rate law will be the same as above.
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- Charles' and Gay-Lussac's Law states that at constant pressure, temperature and volume are directly proportional.
- Charles' Law describes the relationship between the volume and temperature of a gas.
- The law was first published by Joseph Louis Gay-Lussac in 1802, but he referenced unpublished work by Jacques Charles from around 1787.
- This extrapolation of Charles' Law was the first evidence of the significance of this temperature.
- Discusses the relationship between volume and temperature of a gas, and explains how to solve problems using Charles' Law.
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- Boyle's Law describes the inverse relationship between the pressure and volume of a fixed amount of gas at a constant temperature.
- Boyle's Law (sometimes referred to as the Boyle-Mariotte Law) states that the absolute pressure and volume of a given mass of confined gas are inversely proportional, provided the temperature remains unchanged within a closed system.
- The law was named after chemist and physicist Robert Boyle, who published the original law in 1662.
- An animation of Boyle's Law, showing the relationship between volume and pressure when mass and temperature are held constant.
- An introduction to the relationship between pressure and volume, and an explanation of how to solve gas problems with Boyle's Law.
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- Avogadro's Law states that at the same temperature and pressure, equal volumes of different gases contain an equal number of particles.
- Avogadro's Law (sometimes referred to as Avogadro's hypothesis or Avogadro's principle) is a gas law; it states that under the same pressure and temperature conditions, equal volumes of all gases contain the same number of molecules.
- In practice, real gases show small deviations from the ideal behavior and do not adhere to the law perfectly; the law is still a useful approximation for scientists, however.
- By Avogadro's Law, this meant that hydrogen and oxygen were combining in a 2:1 ratio.
- Using Avogadro's Law, this experiment confirmed that 2 hydrogen and 1 oxygen form 1 water molecule.