Which of the following sets of elements have the same number of electrons in outermost shell?

Q. An element with atomic number $17$ is placed in the group $17$ of the long form periodic table. Element with atomic number $9$ is placed above and with atomic number $35$ is placed below it. Element with atomic number $16$ is placed left and with atomic number $18$ is placed right to it. Which of the following statements are correct:
(i) Valency of the element with atomic number $18$ is $0$
(ii) Elements with same valency have atomic number $16,17$ and $18$
(iii) Valency of elements with atomic number $9,17$ and $35$ is one
(iv) Element with atomic number $17$ is more electronegative than elements with atomic number $16$ and $35$

Q. Which of the following elements will have same number of electrons in its outermost shell when compared to the element having atomic number 17.

Q. An element with atomic number $17$ is placed in the group $17$ of the long from periodic table. Element with atomic number $9$ is placed above and with atomic number $35$ is placed below it. Element with atomic number $16$ is placed left and with atomic number $18$ is placed right to it. Which of the following statements are correct?

Q. The number of electrons in 3d orbitals for element with Atomic number 26 is:

Q. Question 21
Which of the following elements will form an acidic oxide?

(a) An element with atomic number 7
(b) An element with atomic number 3
(c) An element with atomic number 12
(d) An element with atomic number 19