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. - it would take minutes to fill the bucket?

370 minutes.

Explanation:

You can calculate the time by using the formula of rate:

         rate = amount / time = number of drops / time

From which you clear the time:

        time = number of drops / rate

The rate and the number of drops are given: 41 drops / minute and 15,000 drops (since that is the number of dropos in 1.00 gallons).

Therefore, time = 15,000 drops / 41 drops / minute = 365.85 minutes

You have to use the correct number of significant figures, which is the least number of significant figures in every factor. 41 has two significant figures, 15,000 also has two significant figures, while 1.00 has three significan figures.

So you must round 365.85 minutes to two significan figures.

That is 370 (365 is round up to 370).

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