Skip to main content
Chemistry LibreTexts

1.S: Matter and Measurement (Summary)

  • Page ID
    91131
  • \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)

    \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)

    \( \newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\)

    ( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\)

    \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)

    \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\)

    \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)

    \( \newcommand{\Span}{\mathrm{span}}\)

    \( \newcommand{\id}{\mathrm{id}}\)

    \( \newcommand{\Span}{\mathrm{span}}\)

    \( \newcommand{\kernel}{\mathrm{null}\,}\)

    \( \newcommand{\range}{\mathrm{range}\,}\)

    \( \newcommand{\RealPart}{\mathrm{Re}}\)

    \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)

    \( \newcommand{\Argument}{\mathrm{Arg}}\)

    \( \newcommand{\norm}[1]{\| #1 \|}\)

    \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)

    \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\AA}{\unicode[.8,0]{x212B}}\)

    \( \newcommand{\vectorA}[1]{\vec{#1}}      % arrow\)

    \( \newcommand{\vectorAt}[1]{\vec{\text{#1}}}      % arrow\)

    \( \newcommand{\vectorB}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)

    \( \newcommand{\vectorC}[1]{\textbf{#1}} \)

    \( \newcommand{\vectorD}[1]{\overrightarrow{#1}} \)

    \( \newcommand{\vectorDt}[1]{\overrightarrow{\text{#1}}} \)

    \( \newcommand{\vectE}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash{\mathbf {#1}}}} \)

    \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)

    \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)

    \(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)

    1.1: The Study of Chemistry

    The Molecular Perspective of Chemistry

    • Matter – physical material of the universe, has mass and takes up space
    • Atoms – the building blocks of matter
    • Molecules – groups of combined atoms

    Why Study Chemistry?

    • important in understanding our world
    • chemistry is the central science
    • many various subjects have some kind of relation to chemistry

    1.2: Classification of Matter

    States of Matter

    • states of matter: liquid, solid, and gas

    Pure Substances and Mixtures

    • pure substance – matter that has a fixed composition and distinct properties
    • substances can be classified as elements or compounds
    • elements – composed of only one atom
    • compounds – two ore more elements
    • mixtures – combination of two or more substances
    • heterogeneous – mixtures that are not uniform throughout
    • homogeneous – mixtures that are uniform throughout; also called solutions

    Separation of Mixtures

    • components in a mixture retain their own properties
    • mixtures can be separated by using the different properties of each substance
    • types of separation: filtration, distillation, chromatography

    Elements

    • over 90% of earth’s crust consists of oxygen, silicon, aluminum, iron, and calcium
    • human body consists of 90% of oxygen, carbon, and hydrogen

    Compounds

    • law of constant composition (law of definite proportions) – elemental composition of a pure compound is always the same

    1.3: Properties of Matter

    • physical properties – properties measured by not changing the identity and composition of the substance
    • chemical properties – the way a substance may change or react to form other substances
    • intensive properties – identify substances
    • extensive properties – amount of substance

    Physical and Chemical Changes

    • physical change results in a change in appearance but not composition
    • changes of state are physical changes
    • chemical changes (chemical reactions) results in a chemically different substance

    1.4: Units of Measurement

    SI Units

    • seven base units
    Prefix Abbreviation Meaning
    Mega- M 106
    Kilo- K 103
    Deci- D 10-1
    Centi- C 10-2
    Milli- m 10-3
    Micro- µa 10-6
    Nano- n 10-9
    Pico- p 10-12
    Femto- f 10-15

    Length and Mass

      • SI base unit for length is the meter (m)
      • Mass is a measure of the amount of material in an object

    Temperature

    • Celsius and Kelvin scales are used commonly in science
    • Both have equal sized units
    • K = °C + 273.15
    • °C = (5/9)(°F –32)
    • °F = (9/5)(°C) + 32

    Derived SI Units

    Volume

    • SI unit is cubic meter
    • Equipment to measure volume accurately : syringes, burets, and pipets

    Density​​​​​​​

    • density = mass/volume

    1.5: Uncertainty in Measurement

    1.5.1 Precision and Accuracy

    • precision – the closeness of individual measurements to one another
    • accuracy – the correctness of individual measurements

    Significant Figures

    • Nonzero digits are always significant
    • Zeros between nonzero digits are always significant
    • Zeros at the beginning of a number are never significant
    • Zeros that fall both at the end of a number and after the decimal point are always significant
    • When a number ends in zeros but contains no decimal point, the zeros may or may not be significant
    • Scientific notation can be used to get the correct significant numbers

    Significant Figures in Calculations

    • the number of significant figures is determined by the number that has the fewest significant figures in the calculation

    1.6: Dimensional Analysis​​​​​​​

    • aid in problem solving
    • conversion factor – fraction where the numerator and denominator are the same quantity

    1.S: Matter and Measurement (Summary) is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

    • Was this article helpful?