Mercury -197 is used for kidney scans and has a half-life of 3 days. If the amount of mercury-197 needed for a study is 1.0 gram and the time allowed for shipment is 15 days, how much mercury-197 will need to be ordered?

32 g

Explanation:

Applying,

R = (R')2ᵃ/ⁿ Equation 1

Where R = Amount of mercury-197 needed to be ordered, R' = amount of mercury-197 needed for the study, a = time allowed for shipment, n = half life.

From the question,

Given: R' = 1 g, a = 15 days, n = 3 days

Substitute these values into equation 1

R = 1(2¹⁵/³)

R = 1(2⁵)

R = 32 g

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s