Chapter 25. Nuclear Chemistry. Nuclear Radiation. Nuclear chem the study of the structure of atomic nuclei and the changes they undergo. No e- / orbitals No e- sharing or transferring No cpds formed No bondings. The Discovery of Radioactivity.
Becquerel accidentally discovered that phosphorescent U salts – even when not exposed to light – produced spontaneous emissions that darkened photographic plates.
Marie Curie (1867–1934) and her husband Pierre (1859–1906) took Becquerel’s mineral sample and isolated the components emitting the rays.
What kind of atoms are radioactive?
3 common types of radiation
What are α particles? How many p+, n0 and e- does each particle carry?
What are the areas that α decay and β decay have in common? (4 bullet pts)
238U → 234Th + 4He
What is radioactive decay? (5 bullet points)
Describe and explain the paths of α, β, and γ radiation under the influence of electric field?
What are β particles? Do they carry any charges?
What is γ radiation? What charge does it carry?
An example of the β decay process is the decay of I-131 into Xe-131 by β-particle emission.
fast-moving e- formed by decomposition of a n0in an atom.
Quick write: why the mass # remain 14 while there is an additional p+?
e.g. unstable has a n0 / p+ ratio of 1.33 : 1, whereas stable elements of similar mass, such as
and , have n0 / p+ ratios ≈1:1
It is not surprising then that undergoes beta decay, as this type of decay decreases the # of n0 in the nucleus.
Note that the atomic # of the product nucleus, , has increased by 1.
The atomic # of decreases by 2 and the mass # decreases by 4 as the nucleus decays into .
Unleash enormous amt of energy e.g. 1 kg of U- 235 (explosion of 20000 tons of dynamite)
A Nuclear Power Plant
Cancer treatment (radiation therapy)
X-rays, MRI, CT scan
A 2-cm thick piece of cardboard placed over a radiation source would be most effect in protecting against which type of radiation?
Which equation correctly represents the alpha decay of polonium-214?
Po 214 0