How do collisions between molecules transfer energy from a system of reacting substances to its surroundings?
A. They cause the potential energy of the system to increase.
B. They cause molecules to flow into the system from the
surroundings.
C. They cause the thermal energy of the surroundings to decrease.
D. They cause heat to flow from the system to the surroundings.
SUB

answer: h+ its less than oh

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