Question

solve question no.(d)please

Answer 1

Chlorine -1 has 18 electrons bcz its accept
one electron.
and Aluminum +3 has 10 electron bcz it donate 3 electrons.... Al has 3 electrons due to which Al is not stable after after donating 3 electrons it becomes stable that's why it losses electrons .. and chlorine accept electron bcz it also need one electron to complete its octet... According to Bohr every atom want itself getting in stable state that's why every atom want to become stable except Noble gas

Answer 2

here there are 10 electrons in AL+3&16 electrons in CL-1 is 18. when in a element there is+ symbol we have to subtract the charge from atomic number. when there is - symbol we have to add the charge from atomic number.
hope this answer helps you