Question

How much aspirin will remain after 12 hours if a person took a single dose of 300 mg? The t½ of aspirin is 3 hours.

a. 100 mg
b. 37.5 mg
c. 18.8 mg
d. No right choice.

Answer 1

Correct answer is option c

Step-by-step explanation:

Formula: Remaining quantity of compound
`$A=P((1)/(2))^(t)/(T)$`

Here,

P = Initial quantity of the compound = 300 mg

t = time that is elapsed = 12 hours

T = half life of the compound = 3 hours

`$\therefore \,Remaining \,quantity \,of \,aspirin=300((1)/(2))^(12)/(3) $\\$=300*(1)/(16) =18.75\approx18.8$`

Hence, 18.8 g aspirin remain after 12 hours.