Deck 14: Trace Evidence Ii: Paint, Glass, and Soil

Question 1

The chemical ingredients of black powder are commonly:

A) potassium nitrate, charcoal, sulfur.
B) aluminum, potassium, nitrate, nitrocellulose.
C) sulfur, carbon, nitrogen.
D) carbon, nitrocellulose, potassium chlorate.
E) none of the above

Answer 1

A

Question 2

What is NOT true about primary explosives?

A) They are used in blasting caps.
B) They are not dangerous to handle.
C) They are very stable.
D) Lead azide and lead styphnate are examples.
E) They will detonate violently.

Answer 2

C

Question 3

___________ explosives detonate almost instantaneously to produce a smashing or shattering effect.

A) low explosives
B) dentoating explosives
C) instantaneous explosives
D) high explosives
E) corrosive explosives

Answer 3

D

Question 4

Which is a homemade explosive that has been used by terrorist organizations in the Middle East?

A) PETN
B) RDX
C) TATP
D) TNT
E) tetryl

Question 5

The most widely used low explosive is:

A) potassium chlorate and sugar.
B) black powder.
C) smokeless powder.
D) all of the above
E) B and C

Question 6

Debris recovered from the site of an explosion is routinely rinsed with ___________ in an attempt to recover explosive residues.

A) ethylene glycol
B) water
C) acetone
D) ethanol
E) none of the above

Question 7

Spot testing for the presence of explosives can be confirmed in the laboratory using:

A) infrared (IR) spectrophotometry.
B) x-ray diffraction.
C) the ion mobility spectrometer (IMS).
D) microscopic identification.
E) A and B

Question 8

An explosive readily detonated by heat or shock is:

A) anfo.
B) primary explosive.
C) dynamite.
D) secondary explosive.
E) black powder.

Question 9

Which is NOT a high explosive?

A) dynamite
B) RDX
C) black powder
D) tetryl
E) TNT

Question 10

An initiating explosive often used in detonators is:

A) PETN.
B) nitrocellulose.
C) lead azide.
D) dynamite.
E) TNT.

Question 11

What is NOT true about x-ray diffraction?

A) It can be applied to all types of materials.
B) It can be used in tandem with other inorganic analysis techniques.
C) It provides information as to how elements are combined in compounds.
D) It provides unique "fingerprints" for each compound analyzed.
E) all of the above

Question 12

Which of the following is not a military explosive?

A) C-4
B) RDX
C) nitroglycerin
D) PETN
E) TNT

Question 13

Which of the following statements is false?

A) Smokeless powder is a low explosive.
B) Thin-layer chromatography is a useful analytical technique for screening debris for explosive residues.
C) Chemicals that supply oxygen are known as oxidizing agents.
D) Potassium chlorate can be mixed with sulfuric acid and sugar to create a low explosive.
E) Dynamite is an initiating high explosive.

Question 14

Most explosives can be recovered from debris for future study by being rinsed with:

A) motor oil.
B) toluene.
C) kerosene.
D) acetone.
E) water.

Question 15

A procedure commonly used as a screening test for explosive residues is:

A) color spot tests.
B) gas chromatography.
C) gas-chromatography-mass spectrometry.
D) thin-layer chromatography.
E) all of the above

Question 16

High explosives can be classified as either ___________ or ___________ explosives.

A) initial; secondary
B) military grade; non-military grade
C) civilian; military
D) primary; secondary
E) low impact; high impact

Question 17

Explosives that decompose at relatively slow rates are classified as:

A) decomposing explosives
B) corrosive explosives
C) high explosives
D) low explosives
E) slow explosives

Question 18

What is NOT true about taggants?

A) They can help the bomb-scene investigator recover useful evidence.
B) They are widely used to help trace an explosive to its last legal possessor.
C) They are color-coded chips that can survive explosions.
D) They carry information regarding where, when and for whom an explosive was manufactured.
E) They are magnetic sensitive and fluorescent.

Question 19

A device used to screen objects for the presence of explosive residues is:

A) x-ray diffraction.
B) mass spectrometry.
C) thin-layer chromatography.
D) ion-mobility spectrometry.
E) infrared spectrophotometry.

Question 20

A chemical used to synthesize the explosive TATP is:

A) aluminum.
B) magnesium.
C) potassium chlorate.
D) hydrogen peroxide.
E) none of the above

Question 21

Briefly explain the classification of explosives.

Question 22

Describe how a forensic scientist would collect physical evidence at the scene of an explosion.

Question 23

For each of the following provide an example of a common type of explosive; commercial, homemade and military.

Question 24

At the crime lab, what procedures to they use to detect and identify explosive residues?