Or which of the following reactions is δh∘rxn equal to δh∘f of the product(s)? you do not need to look up any values to answer this question. check all that apply. view available hint(s) check all that apply. c(s, graphite)+o2(g)→co2(g) co(g)+12o2(g)→co2(g) na(s)+12f2(l)→naf(s) baco3(s)→ bao(s)+co2(g) 2na(s)+f2(g)→2naf(s) na(s)+12f2(g)→naf(s)

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante

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