Question

An element X has atomic number 19. What will be the formula ofj its oxide ?

• A. $X_{2}O$
• B. XO
• C. $XO_{2}$
• D. $X_{2}O_{3}$

Answer 1

Answer: (A)

$X_{2}O$

Answer 2

: Element X has atomic number 19. Its valency will be one. Hence, the formula of its oxide will be $X_{2}O$.

$Z = 19;1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{1}$