Question

a) The atomic number of Aland Cl are 13 and 17 respectively. What will be the number of eles
in Art and Cl​

Answer 1

First of all it's not "ART" it's Al+3 and it's not Cl it's Cl-

Then your answer is as follows....

The atomic number of aluminium is 13. In the outermost orbit of aluminium atom, 3 electrons are present. Hence, after donating 3 electrons its forms Al^{+3}Al

+3

ions, now the number of electrons is 10 and the number of protons is 13. hence, it carries a positive charge.

The atomic number of chlorine is 17. The outermost orbit of chlorine atoms 7 electrons is present. It accepts one electron and forms Cl^-Cl

−

ions, the number of electrons now is 18 and the number of protons is still 17. Hence, it carries a negative charge.

Hope this helps you

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