The diagram shows the electron configuration of an atom of an element for the electrons in the s and p orbitals.
diagram is attached to question.
what is the group number of the element in the periodic table?
a). 1
b). 2
c). 16
d). 17

The correct answer is Option C.

Explanation:

We are given an image having electrons around the nucleus of an atom.

Total number of electrons around the nucleus = 2 + 6 = 8

The electronic configuration of the element having 8 electrons is:  

As, the last electron is entering p-subshell, the element belongs to p-block of the periodic table.

The rule for determining the group number for p-block element is:

Group number = Number of valence electrons + 10

The number of valence electrons = 2 + 4 = 6

Group number = 6 + 10 = 16

Hence, the correct answer is Option C.

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.