Pg. 162-167

Explain the concept of an isotope Understand how elements can be

made radioactive

Provides a tool for identifying and quantitating elements

Investigates how changing the number of subatomic particles unleashing new sources of energy

Emission of radiation that accompanies the spontaneous disintegration of unstable nuclei

Three types•Alpha rays – positively charged particles,

known as Helium without its electrons•Beta rays - electrons•Gamma rays – electromagnetic radiations

similar to X-rays but of a higher frequency and energy

Creates radioactive isotopes Neutron is captured by the nucleus

and a new isotope is formed with one additional neutron

Nuclei is activated and may immediately begin to decompose• Emits radiation

Technique of bombarding specimens with neutrons and measuring the resultant gamma-ray radioactivity

Provides a nondestructive method for identifying and quantitating trace elements

One of the most sensitive methods

Major drawback = expense•Must have access to a nuclear reactor as

well as sophisticated analyzers needed to detect and discriminate gamma-ray emissions

Employed for characterizing trace elements present in metals, drugs, paint, soil, gunpowder residue, and hair

Technique that tells how elements are combined into compounds

Aims a beam of x-rays at a crystal and studies how x-rays interact with the atoms of the substance under investigation

Applied only to a solid, crystalline structure• About 95% of all inorganic compounds are

crystalline in nature

X-rays penetrate the crystal and the beam is reflected by each atomic plane•Reflected beams produce a series of light

and dark bands known as diffraction pattern Each compound is known to

produce its own unique diffraction pattern•“fingerprint” of compound

1. What is radioactivity? 2. What are the three types of

radiation?3. Briefly describe the process of

neutron activation analysis.4. Name two advantages and two

drawbacks of neutron activation analysis.

5. Briefly describe X-ray diffraction.