A piece of metal weighing 12.65 grams absorbs 1090.15 joules of heat energy. The temperature changes from 27°C to 184°C.

a small container that holds a source of energy a solar cell that captures light energy and converts it into electricity a voltaic cell that uses the oxidation of a fuel to produce electricity

explanation:

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