How is an image formed by a plane mirror?
o light bounces off of the mirror and then appears to come from in front of the mirror.
light passes through the mirror and then appears to come from behind the mirror.
o light passes through the mirror and then appears to come from in front of the mirror,
o light bounces off of the mirror and then appears to come from behind the mirror.

i dont know the answe

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