1. Write balanced equations for each of the following processes.

a. Chromium- 51, which targets the spleen and is used as a tracer in studies of red blood cells, decays by electron capture.

b. Iodine-131, used to treat hyperactive thyroid glands, decays by producing a beta particle.

2. In each of the following nuclear reactions, supply the missing particle?
a. ^60Co -> ^60Ni + ?
b. ^97Tc + ? -> ^97Mo
c. ^99Tc -> ^99Ru + ?
d. ^239Pu -> ^235U + ?

3. A chemist wishing to do an experiment requiring 47Ca (half life = 4.5 days) needs 5.0ìg of the
nuclide. What mass of 47Ca must be ordered if it takes 48 h for delivery from the supplier? Assume that the atomic mass of ^47Ca iis 47.0

4. What is the ratio of ^209Pb/^238U by mass in a rock that is 4.5x10^9 years old? (For 238 U, t1/2= 4.5x10^9 years)

Please show work.