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- https://chem.libretexts.org/Courses/Los_Angeles_Trade_Technical_College/Analytical_Chemistry/2%3A_Analytical_Chemistry_2.0_(Harvey)/04%3A_The_Vocabulary_of_Analytical_Chemistry/4.1%3A_Analysis%2C_Determination%2C_and_MeasurementThe first important distinction we will make is among the terms analysis, determination, and measurement. An analysis provides chemical or physical information about a sample. The component of interes...The first important distinction we will make is among the terms analysis, determination, and measurement. An analysis provides chemical or physical information about a sample. The component of interest in the sample is called the analyte, and the remainder of the sample is the matrix. In an analysis we determine the identity, concentration, or properties of an analyte. To make this determination we measure one or more of the analyte’s chemical or physical properties.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Physical_Chemistry_(LibreTexts)/14%3A_Nuclear_Magnetic_Resonance_Spectroscopy/14.03%3A_Proton_NMR_Spectrometers_Operate_at_Frequencies_Between_60_MHz_and_750_MHzThis page discusses the Heisenberg Uncertainty Principle, established by Werner Heisenberg in the mid-1920s. It states that more precise measurement of an electron's position results in greater uncert...This page discusses the Heisenberg Uncertainty Principle, established by Werner Heisenberg in the mid-1920s. It states that more precise measurement of an electron's position results in greater uncertainty in its momentum, due to the wave nature of matter. This principle illustrates fundamental limits in quantum measurements by mathematically expressing the relationship between uncertainties in position and momentum.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/05%3A_Signals_and_Noise_(TBD)When we try to calibrate an analytical method or to optimize an analytical system, our ability to do so successfully is limited by the uncertainty, or noise, in our measurements and by background sign...When we try to calibrate an analytical method or to optimize an analytical system, our ability to do so successfully is limited by the uncertainty, or noise, in our measurements and by background signals that interfere with our ability to measure the signal of interest to us. In this chapter we will consider how we characterize noise, example of sources of noise, and ways to clean up our data by decreasing the contribution of noise to our measurements and by correcting for the presence of backgr
- https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/03%3A_Measurements/3.14%3A_Measurement_UncertaintyThis page discusses how police identify criminals through witness descriptions, focusing on the inherent uncertainty in measurements like height due to the quality of tools and the skill of the measur...This page discusses how police identify criminals through witness descriptions, focusing on the inherent uncertainty in measurements like height due to the quality of tools and the skill of the measurer. It emphasizes that precise tools, such as rulers with detailed markings, can improve measurement accuracy and reduce uncertainty, highlighting their significance in effective assessments.
- https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/03%3A_Measurements/3.02%3A_Metric_PrefixesThis page discusses the significant influence of Latin and Greek on modern scientific and legal terminology, particularly through metric prefixes like kilo and mega. It emphasizes the clarity and ease...This page discusses the significant influence of Latin and Greek on modern scientific and legal terminology, particularly through metric prefixes like kilo and mega. It emphasizes the clarity and ease of communication afforded by the metric system's straightforward conversions based on powers of ten and underscores the importance of using appropriate units and adhering to conventions for metric abbreviations.
- https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/03%3A_Measurements/3.01%3A_SI_Base_UnitsThis page discusses the historical definition and evolution of the yard, initially tied to royal measurements but now standardized. It highlights the challenges of the English measurement system for s...This page discusses the historical definition and evolution of the yard, initially tied to royal measurements but now standardized. It highlights the challenges of the English measurement system for scientific purposes, leading to the adoption of the metric system in 1795 and the International System of Units (SI) established in 1960. Although the U.S. has legally adopted the metric system, it predominantly uses the imperial system.
- https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/04%3A_Atomic_Structure/4.19%3A_Atomic_Mass_UnitThis page highlights the historical importance of standardized measurements in the U.S., particularly in science for consistent data comparison. It establishes the carbon-12 atom as the reference for ...This page highlights the historical importance of standardized measurements in the U.S., particularly in science for consistent data comparison. It establishes the carbon-12 atom as the reference for atomic mass, defining one atomic mass unit as one twelfth of carbon-12's mass. The variations in atomic masses, such as oxygen-16, are discussed due to nucleus interactions, and a mass spectrometer is identified as the tool for measuring these atomic masses.
- https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/03%3A_Measurements/3.13%3A_Percent_ErrorThis page discusses the role of resistors in electrical circuits for regulating voltage and current, emphasizing the significance of understanding their values and error ranges for equipment functiona...This page discusses the role of resistors in electrical circuits for regulating voltage and current, emphasizing the significance of understanding their values and error ranges for equipment functionality. It defines "accepted value" and "experimental value," and demonstrates how to calculate error and percent error using aluminum density as an example. As measurement accuracy diminishes, the percent error rises, indicating reduced precision.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Analytical_Chemistry_2.1_(Harvey)/03%3A__The_Vocabulary_of_Analytical_Chemistry/3.03%3A_Classifying_Analytical_TechniquesThe page discusses analytical techniques used to measure the amount of analyte in a sample, dividing them into two classes: total analysis techniques, which respond to the absolute amount of analyte, ...The page discusses analytical techniques used to measure the amount of analyte in a sample, dividing them into two classes: total analysis techniques, which respond to the absolute amount of analyte, such as gravimetry and titrimetry, and concentration techniques, which respond to analyte concentration, like spectroscopy and electrochemistry.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Physical_Chemistry_(LibreTexts)/25%3A_Solutions_II_-_Nonvolatile_Solutes/25.08%3A_Homework_ProblemsThis page discusses the mid-1920s development of the uncertainty principle by physicist Werner Heisenberg, which states that the precision of a quantum particle's position and momentum is inherently l...This page discusses the mid-1920s development of the uncertainty principle by physicist Werner Heisenberg, which states that the precision of a quantum particle's position and momentum is inherently limited. This principle reveals that decreasing uncertainty in one aspect increases it in the other, stemming from the wave nature of matter. An exercise included illustrates the differences in positional uncertainty between a baseball and an electron.
- https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/16%3A_Solutions/16.07%3A_Percent_SolutionsThis page discusses the variation in numerical recognition across cultures, noting that some do not count beyond three. It highlights American cultural practices in expressing solution concentrations,...This page discusses the variation in numerical recognition across cultures, noting that some do not count beyond three. It highlights American cultural practices in expressing solution concentrations, defining concentrated and dilute solutions, and explaining how concentrations can be represented in mass percent and volume percent. The page includes examples to illustrate methods for calculating these percentages.
