oil drop experiment

Examples of oil drop experiment in the following topics:

• Millikan's Oil Drop Experiment

  • The oil drop experiment calculated the charge of an electron using charged oil droplets suspended in an electric field.
  • In 1909, Robert Millikan and Harvey Fletcher conducted the oil drop experiment to determine the charge of an electron.
  • The figure below shows a simplified scheme of Millikan's oil drop experiment.
  • Ordinary oil would evaporate under the heat of the light source, causing the mass of the oil drop to change over the course of the experiment.
  • Robert Millikan and Harvey Fletcher used the oil drop experiment.

• Present Sources of Energy

  • Oil was the most popular energy fuel, and oil and coal combined represented over 60% of the world energy supply in 2008.
  • However, with the advent of the automobile, airplanes, and the growing use of electricity among consumers, oil became the dominant fuel during the 20th century.
  • The growth of oil as the largest fossil fuel was further enabled by steadily dropping prices from 1920 until 1973.
  • However, after the oil shocks of 1973 and 1979, during which the price of oil increased from $5 to $45 per barrel, there was a shift away from this particular resource.
  • Japan, which bore the brunt of the oil shocks, has also made spectacular improvements to its technology.

• Liquid to Gas Phase Transition

  • In a very small drop, the liquid surface is curved in such a way that each molecule experiences fewer nearest-neighbor attractions than is the case for the bulk liquid.
  • The outermost molecules of the liquid are bound to the droplet less tightly, and the drop has a larger vapor pressure than does the bulk liquid.
  • If the vapor pressure of the drop is greater than the partial pressure of vapor in the gas phase, the drop will evaporate.
  • A bubble is a hole in a liquid; molecules at the liquid boundary are curved inward, so they experience stronger nearest-neighbor attractions.

• Avogadro's Law: Volume and Amount

  • In particular, the existence of diatomic molecules of elements such as H2, O2, and Cl2 was not recognized until the results of experiments involving gas volumes was interpreted.
  • When chemists revisited their water experiment and their hypothesis that $HO \rightarrow H + O$, they discovered that the volume of hydrogen gas consumed was twice that of oxygen.
  • Run the model and select different numbers of molecules from the drop-down menu.
  • Using Avogadro's Law, this experiment confirmed that 2 hydrogen and 1 oxygen form 1 water molecule.

• Acid-Base Titrations

  • Before you begin the titration, you must choose a suitable pH indicator, preferably one that will experience a color change (known as the "end point") close to the reaction's equivalence point; this is the point at which equivalent amounts of the reactants and products have reacted.
  • Place an accurately measured volume of the analyte into the Erlenmeyer flask using the pipette, along with a few drops of indicator.
  • Small increments are added from the burette until, at the end point, one drop changes the indicator color permanently.

• Capillary Action

  • The molecules in any sample of matter experience intermolecular forces, which are attractive or repulsive forces between atoms or molecules within the sample.
  • The molecules in a sample of water in contact with a glass surface experience attractive forces toward the glass molecules.
  • When considering how liquids will behave on surfaces, if the liquid molecules are strongly attracted to the solid molecules then the liquid drop will completely spread out on the solid surface.

• Constant-Pressure Calorimetry

  • Data collected during a constant-pressure calorimetry experiment can be used to calculate the heat capacity of an unknown substance.
  • A student heats a 5.0 g sample of an unknown metal to a temperature of 207 $^\circ$C, and then drops the sample into a coffee-cup calorimeter containing 36.0 g of water at 25.0 $^\circ$C.

• Signal Strength

  • Experimentally, one simply adds a drop of heavy water to a chloroform-d solution of the compound and runs the spectrum again.
  • The case of 4-hydroxypent-3-ene-2-one (the enol tautomer of 2,4-pentanedione) not only illustrates this characteristic, but also provides an instructive example of the sensitivity of the nmr experiment to dynamic change.
  • Since only one strong methyl signal is observed, we must conclude that the interconversion of the enols is very fast-so fast that the nmr experiment detects only a single time-averaged methyl group (50% α-keto and 50% allyl).