The elements in which $s$ and $p$-orbitals are present are known as:

Which of the following represents the correct order of acidic strength?

In the periodic table,metallic character of the elements shows which one of the following trends?

How does the chemical reactivity change as we move from left to right across a period in the periodic table?

Match the following:

Oxide	Nature
$a$. $CO$	$i$. Basic
$b$. $BaO$	$ii$. Neutral
$c$. $Al_2O_3$	$iii$. Acidic
$d$. $Cl_2O_7$	$iv$. Amphoteric

Which of the following is the correct option?

The oxide of a metal $(R)$ can be reduced by the metal $(P)$,and metal $(R)$ can reduce the oxide of metal $(Q)$. Then the decreasing order of the reactivity of metals $(P)$,$(Q)$,and $(R)$ with oxygen is: