if i initially have a gas at a pressure of 12.0atm, a volume of 23 liters and a temperature of 20.0 °c and then i raise the pressure to 140kpa and increase the temperature to 80.0°c what is the new volume of gas

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.

the answer is 75.0%.

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

the answer is a! (2.9 x 10^-18 j) hope i could someone. : )