Question

Valency of an element X is 3. Write the chemical formula of its oxide?​

Answer 1

Answer:

element X is Aluminium

• It's oxide is

Answer 2

Answer:

$\huge{\textsf{\green {{X}_{2}{O}_{3}}}}$

Explanation:

"Oxygen" is a $\blue{divalent}$ element. Hence, it requires two electrons to get octet.

But, here the given element is "X" which is a $\blue{</strong><strong>t</strong><strong>r</strong><strong>i</strong><strong>valent}$. It means, it can donate three electrons.

Since, oxygen requires only two electrons , two $\blue{three \: oxygens}$ combines with the element. It results in the formation of X2O3

From Criss-cross method:-

${X}^{+3} \: \: \: {O}^{-2}$

Shift of charges between the elements takes place.. which forms X2O3