Because negatives are on the left and positives are on the right , if it was .0100 +x it would move to the right since +x implies that the x is positive.
Oxidation numbers is the right answer
This type of formula is use in chemistry it has Iron ,Sodium, Hydroxyl and Chloride unit s in the equation.
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<u>Answer:</u> The electronic configuration of gallium is written below and number of valence electrons is 3.
<u>Explanation:</u>
Electronic configuration is defined as the representation of electrons around the nucleus of an atom.
Number of electrons in an atom is determined by the atomic number of that atom.
Valence electrons are defined as the electrons present in the outermost shell of an atom.
We are given:
An element Gallium having atomic number as 31.
Number of electrons = 31
Electronic configuration of Gallium is: 
This element has 3 electrons in its outermost shell. So, the number of valence electrons is 3
Hence, the electronic configuration of gallium is written below and number of valence electrons is 3.