Light vs. Electron Microscope and Solution Calculations

Flashcards covering the history of microscopy, the differences between light and electron microscopes, and laboratory reagent calculations.

Zacharias Jansen

A Dutch spectacle maker who, along with his father Hans, started experimenting with lenses in the 1590's.

Antonie van Leeuwenhoek

A Dutch draper and scientist (1632-1723) who was one of the pioneers of microscopy and the first man to make and use a real microscope.

Micrographia

Robert Hooke's most famous work, notable for its stunning illustrations drawn by himself.

Resolving Power

The ability of a microscope to differentiate between two close together objects; higher resolution allows objects to be seen as separate points.

Simple Microscope

A microscope that uses a lens or set of lenses to enlarge an object through angular magnification alone, historically magnifying up to $266\times$.

Dissecting Microscope

A microscope with magnification between $10\times$ and $40\times$; it is not used for cellular level and can view living or non-living specimens.

Compound Microscope

A microscope that uses an objective lens to collect light and focus a real image; modern versions can magnify an object from $1000\times$ to $2000\times$.

Light Microscope (Radiation Source)

Uses light rays transmitted through lenses to the eye; limited to a resolution of approximately $0.2\text{ nm}$ ($200\text{ nm}$).

Electron Microscope

A microscope that uses a beam of accelerated electrons as a source of illumination instead of light.

Scanning Electron Microscope (SEM)

A microscope designed to create detailed 3D images of the surfaces of tiny objects with a resolution of $1\text{ nm}$ and magnification up to $200,000\times$.

Transmission Electron Microscope (TEM)

The most powerful electron microscope that fires a beam of electrons through a specimen to see interior structures, magnifiying up to $500,000\times$ or more.

Molar Mass of Sucrose ($C_{12}H_{22}O_{11}$)

Calculated as $(12 \times 12) + (22 \times 1) + (11 \times 16) = 342\text{ g/mole}$.

Molar Mass of $H_2SO_4$

Calculated as $(2 \times 1) + (32 \times 1) + (16 \times 4) = 98\text{ g/mole}$.

Molarity ($M$) Formula

$M = \frac{\text{moles}}{\text{liters}}$ where $\text{moles} = \frac{\text{grams}}{\text{MW}}$.

Electron Microscope Limitations

Expensive, requires extensive training, samples must be dead/in a vacuum, and produces black and white or false color images.