Please explain how I am supposed to do this I literally have no idea and this is due today Mr. B weighs out 22.8 grams of cobalt (II) chloride, then dissolves that CoCl2 in 500 mL of water. What is the concentration of his cobalt (II) chloride solution?
3.51 M CoCl2
0.351 M CoCl2
0.176 M CoCl2
0.0456 M CoCl2

they vary. it used to be meat, grain, bread, candy, beverages, donuts, and fruits/vegetables. now they added exercise in.

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