Electron Microscopes

Question 1

Instead of a beam of light like in traditional microscopes, electron microscopes use a beam of…

Answer 1

electrons to study specimens

Question 2

What do electrons have in which they can be used to create higher resolution images?

Answer 2

Higher wavelength

Question 3

What are the two types of electron microscopes?

Answer 3

Scanning (SEM) and Transmission (TEM)

Question 4

In both types of electron microscopy…

Answer 4

a beam of electrons is focused by a magnet towards a specimen

Question 5

What must happen to the specimens?

Answer 5

They must be stained or coated with metal and placed in a vaccum

Question 6

This preparation means electron microscopy can only be used to study…

Answer 6

dead specimens

Question 7

What happens in scanning electron microscopy?

Answer 7

The electron beam hits the specimen and is scattered into a detector

Question 8

This means the microscope image can be…

Answer 8

3D, but is at a low resolution and magnification

Question 9

What happens in transmission electron microscopy?

Answer 9

The electron beam travels through the specimen to a detector

Question 10

This allows for higher…

Answer 10

Resolution and magnification than SEM, but a 2D image

Question 11

SEM - Electron Beam, 3D dimension, X200,000 Max Magnification, 20nm Max Resoluton —> so what is TEM?

Answer 11

TEM - Electron Beam, 2D Dimension, X2,000,000 Max Magnification, 0.1nm Max Resolution