Solve the problems. express your answers to the correct number of significant figures. 0.09 + 1.324 = 41.0 + 78.3 =water drips from a faucet at a rate of 41 drops/minute. assuming there are 15,000 drops in a gallon, how many minutes would it take for the dripping faucet to fill a 1.00‑gallon bucket? express your answer to the correct number of significant figures. how many minutes to fill the bucket.

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