When the length of a chemical bond is short...

a. an electron is held tighter and the bond is weaker

b. an electron is held loosely and the bond is weaker

c. an electron is held tighter and the bond is stronger

d. an electron is held loosely and the bond is stronger

Option c. is correct

Explanation:

A chemical bond enables the formation of chemical compounds depending on the nature of the participating atoms like atoms, ions or molecules.

These are formed as a result of the force of attraction between oppositely charged ions.

It is formed by the overlapping of the atomic orbitals of the two atoms.

When the length of a chemical bond is short an electron is held tighter and the bond is stronger

the electronic configuration of an atom with eight electrons is 1s²2s²2p⁴. the orbital diagrams are shown in the figure.

as per the hunds rule:

1. electrons tend to avoid being in the same orbital as per as practicable.

2. electrons in different orbitals of the same energy will have their spin parallel.

this can be illustrated from the multiplicity of the orbitals of the atom. as there are four electrons in the p orbital and p orbital has 3 sub-shells. the electrons can be fed in different ways as shown in the figure but the correct orbital diagram will be as per the hunds rule.

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