Select the correct answer.
In which location would a free neutron from a decaying U-235 atom be most likely to cause another atom to split?
OA
in a sample of naturally occurring uranium
B.
in a sample of enriched uranium
O C.
in a sample of rock or soil
D.
in the Sun's core
E.
in a distant star

B.  in a sample of enriched uranium

Explanation:

Decaying of U-235 atom is a process of nuclear fission. In this process a neutron is bombarded on U-235 and the uranium atom captures the neutron and divide immediately to release neutron. With the release of one neutron another nuclear fission process starts.

The free neutron is then split in a sample of enriched uranium because splitting nucleus releases high energy and enrich uranium increases the percentage of uranium-235 which further undergoes fission. This is why enrich uranium samples are used in atomic reactors.

Hence, the correct option is B.

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