Suppliers of radioisotopically labeled compounds usually provide each product as a mixture of labeled and unlabeled material. Unlabeled material is added deliberately as a carrier, partly because the specific activity of the carrier-free product is too high to be useful and partly because the product is more stable at lower specific activities. Using the radioactive decay law, calculate the following.
(a) Te specific activity of carrier-free [32P]-orthophosphate, in mCi / mmol.
(b) Te fraction of H atoms that are radioactive in a preparation of uniform-label [3H]-leucine, provided at 10 mCi / mmol.