CHEM 150
Assignment #6
(Due Monday, Jan. 27th)
1) Write an equation to describe the chemical reaction for each of the following buffering actions:
a. The response of a HPO42-/PO43- buffer to the addition of OH- ions.
b. The response of a HF/F- buffer to the addition of OH- ions
c. The response of a HCN/CN- buffer to the addition of H3O+ ions
d. The response of a H3PO4/H2PO4- buffer to the addition of H3O+ ions
2) What is the pH of a HCN/NaCN buffer that is 0.250 M in HCN and 0.260 M in NaCN? Ka for the acid is 2.95 x 10-6.
3) Supply the missing symbol for each of the following nuclear equations:
a.
b.
c.
4) Write nuclear equations to describe each of the following radioactive decay processes:
a. Cadmium-120 undergoes beta emission.
b. Alpha emission produces Plutonium-241 as a product.
5) The half-life of Strontium-90 is 28 years. How many grams of this nuclide in a 4.00-g sample will remain after
112 years?
6) Supply the missing nuclear symbol in each of the following bombardment reactions:
a.
b.
7) How many neutrons are produced in each of the following U-235 fission reactions? Write the balanced nuclear
equation in each case.
a.
(s)
b.