Question

Identify the correct order of acidic strengths of $C{O}_2,CuO,CaO\text{and}{H}_{2}O$

• A. $CaO<CuO<H_{2}O<C{O}_2$
• B. $H_{2}O<CuO<CaO<C{O}_2$
• C. $CaO<H_{2}O<CuO<C{O}_2$
• D. $H_{2}O<C{O}_2<CaO<CuO$

Answer 1

The correct option is A $CaO<CuO<H_{2}O<C{O}_2$

We know that non - metallic oxides are acidic and metallic oxides are basic in nature.

Thus, the order of acidic character is $CaO<CuO<H_{2}O<C{O}_2$.

$H_{2}O$ is an amphoteric oxide and $C{O}_2$ is a non metal oxide.
$CaO\text{and}CuO$ are metallic oxides.

Again basicity of oxides decreases as we move from left to right in a period of the periodic table, and conversely acidic character icreases. Thus $CuO$ is more acidic in nature compared to $CaO$