Answer :
Atomic number = 79
Atomic mass = 197
Number of orbits = 6
Number of neutrons = 118
Number of electrons in (n=3) = 18
Number of valence electrons = 1
Explanation :
According to the given image of gold metal,
The atomic number is located above the element symbol, in the upper left-hand of the corner of square (Atomic number = 79). The atomic number tell us about that how many number of protons are present in element. And the number of protons is equal to the number of electrons.
The atomic mass is located below symbol of element. (Atomic mass = 197)
To find the number of neutrons, we will need of the atomic number and the atomic mass. This means,
The number of neutrons = Atomic mass - Atomic number
The number of neutrons = 197 - 79 = 118
The electronic configuration of gold element (Au) = [tex]1s^{2} 2s^{2} 2p^{6}3s^{2}3p^{6}3d^{10} 4s^{2} 4p^{6} 4d^{10} 5s^{2} 5p^{6} 4f^{14}5d^{10}6s^{1}[/tex]
Number of orbits = Number of energy level (n) = 6
where, 'n' is principle quantum number
Number of electrons in (n=3) = 18
Number of valence electron = 1 ( according to electronic configuration, the valence shell in gold is [tex]6s^{1}[/tex])
