A buffer solution is prepared by adding NH4CI to a solution of NH3 (ammonia).
NH3(aq) + H2O(l) = NH4+ (aq) + OH-(aq)
What happens if HCl is added?

A) shifts to reactants
B)remains the same
C) shifts to products

d. temperate deciduous forest

the answer to this question is 3.

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