The isotope 'sr has a half-life of 28.8 years. what is the activity, measured in atoms/second, of a 50 mg sample of "sr? (10 pts.)

The activity of 50mg of Sr is

Explanation:

Every nuclear disintegration follows the first order rate, thus the half-life (t1/2) is where k is the constant of the reaction.

Considering 1 year equals 3.15x107 seconds

For Sr with t1/2 = , the constant of the reaction is

The activity (A) of a nucleus is where N is the number of nucleus. Sr molecular mass is 87.6g/mol and every mol contains 6.023x1023 atoms, thus

Therefore, the activity of 50mg of Sr is

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.