The pesticide DDT was first made by a chemical company in 1939 and became widely used worldwide. Evidence that DDT builds up in animal tissues and may cause health problems such as cancer and damage to organs, as detailed in Rachel Carson’s book Silent Spring, resulted in DDT being banned in the US in 1972. How do you suppose science and society were affected by the ban of DDT?

1.43 x 10^-11 j the guy commented the awnser just making sure u see it .

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol