Module 4 - SET B (Part 2)

Question 1

technique for determining the relative positions of atoms within a crystal

Answer 1

X-ray crystallography

Question 2

orderly, three-dimensional, repeating arrangement of atoms or molecules

Answer 2

crystal

Question 3

True or False: conditions can be arranged so the intermolecular forces cause the molecules to line up in an organized, repeating manner.

Answer 3

True

Question 4

provides very precise, high-resolution structural information for molecules in a crystal

Answer 4

x-ray crystallography

Question 5

used to discover that DNA is a double helix

Answer 5

x-ray crystallography

Question 6

What is the great advantage of x-ray crystallography?

Answer 6

High-resolution it can provide.

Question 7

What is the disadvantage of x-ray crystallography?

Answer 7

molecules need to be in crystalline form in order for it to work

Question 8

true or false: not all molecules can be crystalized so there are other techniques to know their structural information

Answer 8

true

Question 9

On what principle does the x-ray crystallography operates?

Answer 9

Principle of Diffraction

Question 10

occurs when the light waves pass through an ordered arrangement of openings (as one finds in a crystal) and interfere with each other on the other side.

Answer 10

diffraction

Question 11

acts a new starting point for the waves

Answer 11

openings

Question 12

when waves meet in phase with one another, the peaks from one wave come together with peaks from the other wave, and troughs from one wave come together with the troughs from the other wave

Answer 12

constructive interference

Question 13

peaks become higher and the troughs become lower

Answer 13

constructive interference

Question 14

when waves out of phase, a peak and trough come together

Answer 14

destructive interference

Question 15

waves flatten out and lower the intensity of radiation

Answer 15

destructive interference

Question 16

technique that takes advantage of the behavior of electromagnetic waves when they encounter atoms or molecules arranged in a regular, repeating structure

Answer 16

x-ray crystallography

Question 17

True or False: X-rays are a type of electromagnetic radiation, as is light

Answer 17

true

Question 18

True or False: X-rays are visible to the naked eye

Answer 18

false, it’s not visible

Question 19

How can we measure the intensity of x-rays?

Answer 19

use of phtographic film and other detection devices