Which of the following classifications is not correct? (chemistry not math wrong subject) -- change adminnoble gases - 8 valence electronshalogens - 6 valence electronstransition metals - number of valence electrons variesalkali rare earth metals - 2 valence electrons

Halogens - 6 valence electrons

Step-by-step explanation:

Valence electrons are the number of electrons present in the outermost shell of the atom.

Noble gases have 8 valence electrons which is the maximum and are stable. They are inert by nature since they don't have to combine with any other element to attain stability.

Halogens have 7 valence electrons. They are high electronegative and have great attraction for electrons so that they can attain stability by forming the octet.

The valence electrons in transition metals varies as a group of columns are named transition metals.

Alkali earth metals has two valence electrons.

Hence the incorrect statement here is

Halogens - 6 valence electrons

step-by-step explanation:

1. practice, practice & more practice

2. review errors

3. master the key concepts

do not try to memorise the processes.

4. understand your doubts.

5. create a distraction free study environment

6. create a mathematical dictionary

7. apply maths to real world problems.

what i would say the best answer is a. 40.5