In Chemistry, there are specific rules for writing the formulas of ionic compounds having a given name. One or more of these formulas are breaking the rules. Select all the rule breakers. Tap to select or deselect an option. Select all the rule breakers. barium potassium oxide magnesium chloride oxide Ba,02 ko MgCl

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