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2: Measurements, Unit Conversions, and Density

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    521694
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    • 2.1: Expressing Numbers - Scientific Notation
      Scientific notation is a system for expressing very large or very small numbers in a compact manner. It uses the idea that such numbers can be rewritten as a simple number multiplied by 10 raised to a certain exponent, or power.  Scientific notation expressed numbers using powers of 10.
    • 2.2: Units for Measurements
      Measurements provide quantitative information that is critical in studying and practicing chemistry. Each measurement has an amount, a unit for comparison, and an uncertainty. Measurements can be represented in either decimal or scientific notation. Scientists primarily use the SI (International System) or metric systems. We use base SI units such as meters, seconds, and kilograms, as well as derived units, such as liters (for volume) and g/cm3 (for density).
    • 2.3: Density
      Density is a physical property that is defined as a substance’s mass divided by its volume. Density is usually a measured property of a substance, so its numerical value affects the significant figures in a calculation. Notice that density is defined in terms of two dissimilar units, mass and volume. That means that density overall has derived units, just like velocity.
    • 2.4: Expressing Numbers - Significant Figures
      Significant figures properly report the number of measured and an estimated digit in a measurement. There are rules for applying significant figures in calculations.
    • 2.5: Converting Units-Dimensional Analysis
      The ability to convert from one unit to another is an important skill. A unit can be converted to another unit of the same type with a conversion factor.
    • 2.6: Solving Multistep Conversion Problems
      Sometimes you will have to perform more than one conversion to obtain the desired unit.
    • 2.7: Dosage Calculations I
      Conversion factors are important in calculating dosages of medications administered to patients.
    • 2.8: Dosage Calculations II
      Drug dosage calculation is required if the physician’s order is different from what is available. We will see examples where the medications are administered as fluids or tablets.
    • 2.E: Measurements, Unit Conversions, and Density (Exercises)
      This problem set is based on the topics covered in Chapter 2.


    This page titled 2: Measurements, Unit Conversions, and Density is shared under a CC BY license and was authored, remixed, and/or curated by Sol Parajon Puenzo (Cañada College) .

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