Part One: Experimental Design In this section, you will think about what type of experiment to set up. Remember, you are NOT completing the experiment, only designing it. If you want to review the scientific method first, use this tutorial. Use these guiding questions to help you design the experiment. Answer each question below:
What hypothesis will the experiment test?
What are the variables?
giving brainlest to who evder answers questions right!!!

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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

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