An ammonia (nha) solution composed of 20.0 g nha for every 80.0 g water flows into a 480.0 gallon tank mapdb the density of this solution is p 0.9229 g/ml. what is the molarity of this solution? number mol nh, l if you need to fill the 480.0 gallon tank in 160.0 s, what is the flow rate of amimonia solution into the tank? number m'/s how many moles of ammonia are in the tank when it is filled? number mol nh, before the ammonia solution enters the tank, it flows through a 31.0 m long pipe with a cross-sectional diameter of 10.0 cm. at the flow rate you calculated above, how long would it take, on average, for the solution to flow between the pipe inlet and outlet?

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

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