Chapter 14 Chapter Review

What is the difference between low explosives and high explosives?

a low explosive has a detonation less than 1000 meter per second, and a high explosive has a detonation greater than 1000 meters per second

What types of explosives have largely have replaceddynamite for industrial uses? What are the advantages?

aamonium nitrate, more stable easier to control

In recent years, dynamite has been replaced commercially by

ammonium nitrate-based explosives

After bomb-scene debris has been examined microscopically, the next step is to

rinse the recovered debris with acetone to separate the debris from explosive material

What produces the violent physical disruption associated with an explosion?

sudden build up of gas

The single most important step in the detection and analysis of explosive residues is

the collection of appropriate samples from the explosion scene

What is the most obvious postexplosion characteristics of a high or contained low explosive?

the presence of a crater at the origin of the blast

t/f: Military high explosives include RDX, TNT, and PETN

true

t/f: the ion mobility spectrometer has become a widely used instrument for detecting the presence of explosive residues on objects

true

t/f: the most widely used explosives in the low-explosives group are black powder and smokeless powder

true

t/f: the speed at which explosives decompose varies greatly from one to another and permits their classification as high and low explosives

true

Name two confirmatory tests for the presence of intact explosives located in debris

x-ray defraction, spectrophotometry

Low explosives decompose at rates that vary up to

1000 meters per second

What is a safety fuse and what is it used for?

A safety fuse is a cord containing a core of black powder and its used to carry a flame at a uniform rate to an explosive charge

What is ANFO?

An explosive consisting of ammonium nitrate soaked in fuel oil.

Which is the most popular and powerful military explosive?

C-4

Which type of explosive is classified into two groups, primary and secondary?

High Explosives

What are the two classes of high explosives? What is the difference between the two classes?

Primary and Secondary- the difference is a primary explosive is easily detonated by heat shock or friction. A secondary is insensitive to that

What are the main ingredients are in straight dynamite?

Pulp, nitrogylcerin, sodium nitrate and a stabilizer

What is a taggant? What purpose do taggants serve?

basically a chip to put in a bomb to identify what was used to make it. It can withstand an explosion so it can track it, not used in the usa

What is a detonator?What is the most composition of most detonator?

blasting caps are composed of copper or aluminum cases filled with lead azide.

List 3 procedures commonly used as screening tests for explosive residues.

color spot test, thin layer chromatography, mass spec

What is the difference between deflagration and detonation?

deflagration-low intensity pressure detonation- high speed shock wave, intense

t/f:Debris and particles collected from different areas at an explosion site are to be packaged in separate plastic containers

false

What is the first procedure typically used to analyze bomb-scene debris that arrives in the laboratory?

first examined microscopically to detect particles of unconsumed particles.

What ingredients are required to create a low explosive?

fuel and an oxidizing agent

how are soil and other soft loose materials collected at the scene of an explosion best stored?

in an airtight container