2: The Numerical Side of Chemistry
- Page ID
- 531715
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)- 2.1: Taking Measurements
- This page underscores the significance of quantification in science, especially chemistry, through the use of numbers and units. Emphasizing clarity, it highlights the need for both components in measurements, using examples like distance and temperature. Additionally, it advocates for a thorough understanding of specific units in chemistry and prepares the reader for the upcoming discussion on rules for expressing numbers in scientific contexts.
- 2.2: Significant Figures - Writing Numbers to Reflect Precision
- This page covers the concepts of significant figures and measurement uncertainty in scientific measurements. It explains that significant figures include all certain digits and one uncertain digit, highlighting rules for identifying them. The text also discusses how measurement uncertainty relates to the quality of tools, and it classifies measurement sets based on their precision and accuracy.
- 2.3: Scientific Notation - Writing Large and Small Numbers
- This page covers scientific notation in chemistry, detailing how to express large or small numbers by adjusting the decimal point and setting the exponent. It outlines rules for arithmetic operations with scientific notation, emphasizing that addition and subtraction require matching exponents, while multiplication adds exponents and division subtracts them. Examples illustrate these concepts for better understanding.
- 2.4: Significant Figures in Calculations
- This page addresses the proper use of significant figures in mathematical operations, detailing rules for rounding and precision in addition, subtraction, multiplication, and division. It emphasizes matching the final result to the least precise measurement, retaining extra digits in intermediate results for accuracy, and adjusting numbers based on rounding rules. Examples are provided to clarify these principles.
- 2.5: The Basic Units of Measurement
- This page covers measurement systems in chemistry, particularly the metric system and its advantages over the English system. It outlines the International System of Units (SI), established in 1960, including seven base units such as meter and kilogram. Common metric prefixes like milli-, centi-, and kilo- are explained, showcasing their relationships to base units. The overall emphasis is on the metric system's simplicity and universality in scientific measurements.
- 2.6: Temperature - Random Motion of Molecules and Atoms
- This page distinguishes between temperature, a measure of an object's thermal energy, and heat, the transfer of energy between objects at different temperatures. It covers the Fahrenheit, Celsius, and Kelvin scales, explaining their freezing and boiling points of water, as well as conversion methods. Notably, the Kelvin scale's uniqueness is emphasized through its absolute zero starting point.
- 2.7: Density
- This page discusses density as a key property defined by mass divided by volume, which remains consistent for pure substances regardless of size. It highlights variations in density among substances, affecting their behavior in mixtures, and explains units of measurement. The page emphasizes density's role as a conversion factor between mass and volume and provides practical examples for calculating density, showcasing its importance in problem-solving.
- 2.8: Problem Solving and Unit Conversions
- This page emphasizes the role of conversion factors in unit conversions essential for chemistry and physics, detailing the process of dimensional analysis. It provides examples ranging from basic to complex conversions, underscoring the importance of maintaining proper units and addressing significant figures.
- 2.9: Metric Unit Conversions
- This page explains converting track laps to distance using dimensional analysis and metric conversions, emphasizing metric prefixes. It includes examples for calculating milliliters for experiments and converting centimeters to micrometers. The importance of unit sizes and proper cancellation during conversions is highlighted, alongside a review section for additional practice on unit conversions.
- 2.10: Solving Multi-step Conversion Problems
- This page covers multi-step unit conversions using conversion factors and includes examples like kilometers to millimeters. It stresses the importance of significant figures in these conversions. The page also provides an overview of the pharmacist profession, detailing their educational requirements and contribution to medication management and patient care, highlighting the significance of chemistry and biology in their work.
- 2.11: Units Raised to a Power
- This page covers the conversion of area and volume units using powers of 10, highlighting the importance of applying the same power to both the number and the unit. It includes an example of converting square centimeters to square meters and presents a problem-solving scenario for calculating a sphere's volume in cubic centimeters from inches. An exercise encourages further practice with converting surface area from square miles to square kilometers.
- 2.12: Derived Units
- This page explains derived units formed from SI base units, focusing on dimensional analysis essential for unit conversion, with examples linking cubic millimeters, cubic centimeters, and liters. Additionally, the page concludes with review questions to reinforce understanding of derived units and conversions.


