Which of the following salts has a $pH$ less than $7$? Why?

Differentiate between strong electrolytes and weak electrolytes. Mention two examples each.

What happens when metal oxide reacts with water?

During the preparation of hydrogen chloride gas on a humid day,the gas is usually passed through the guard tube containing calcium chloride. The role of calcium chloride taken in the guard tube is to

How is the $pH$ of a solution of an acid influenced when it is diluted?

Fill in the missing data in the following table:

Name of the salt	Formula	Base	Acid
$(i)$ Ammonium chloride	$NH_{4}Cl$	$NH_{4}OH$	-
$(ii)$ Copper sulphate	-	-	$H_{2}SO_{4}$
$(iii)$ Sodium chloride	$NaCl$	$NaOH$	-
$(iv)$ Magnesium nitrate	$Mg(NO_{3})_{2}$	-	$HNO_{3}$
$(v)$ Potassium sulphate	$K_{2}SO_{4}$	-	-
$(vi)$ Calcium nitrate	$Ca(NO_{3})_{2}$	$Ca(OH)_{2}$	-