The half-life of a substance is the amount of time it takes for half of the amount of substance to decay. The half-life of a pesticide is 2 years. Initially there are 500 grams of pesticide. How much pesticide is left after 10 years? Round to the nearest hundredth.

15.625 grams

Step-by-step explanation:

The decay is First order reaction

The half life of the first order reaction is given by

T(1/2)  = ㏑2/K

where K is the reaction constant for the first order reaction

T(1/2) = 2

2 = ln 2 /K

K = ln2/2

The equation of the first order reaction is given by

Kt = ln ()

where

t = time = 10years

Ro = initial concentration

R = amount left after time t

upon substituting the values

5ln2 = ln (500/R)

ln = ln (500/R)          (a*lnb = ln)

R = 500/32  = 15.625grams

Therefore the amount of pesticide left after 10 years is 15.625grams

step-by-step explanation:

if you want to solve percent error follow these steps.

1. subtract the accepted value from the experimental value.

2. take the absolute value of step 1.

3. divide that answer by the accepted value.

4. multiply that answer by 100 and add the % symbol to express the answer as a percentage.

if you want to solve percent of change just do this.

1. work out the difference (increase) between the two numbers you are comparing.

2. divide the increase by the original number and multiply the answer by 100. if your answer is a negative number then this is a percentage decrease.

hope this : )

sorry i just need to anwers this to get points

step-by-step explanation: