Unit test
unit test review
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scientists described light as a wave because the results of many experiments with light demonstrated that light behaves as a
wave. light is now described as having properties of both a wave and a particl
what is the most likely reason why this change was made?
enough scientists voted to accept the change,
data collected from many experiments could not be explained using waves
a well-known scientist published a paper that described light as a particle.
a single experiment's results demonstrated both wave and particle properties

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