Chemistry: Atoms and elements. having trouble figuring out how to find out what element these atoms represent any help will be apreciated.

Elements are types of atoms that have a unique number of protons. In fact, from left to right, the periodic table is arranged by the number of protons that each element contains. oms make up matter. An atom is the smallest unit of matter that retains all of the chemical properties of an element.

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