Name the sodium compound which is used for softening hard water.
$ Mg(OH)_2 $
$ Ca{(OH)} _{3} $
$Al_{2} O _{3} $
$Na _{2} CO _{3} \cdot 10 H _{2} O$
Plaster of Paris should be stored in a moisture-proof container. Explain why ?
Fresh milk has a $pH$ of $6$. How do you think the $pH$ will change as it turns into curd ? Explain your answer.
Why do acids not show acidic behaviour in the absence of water ?
What is the common name of the compound $CaOCl_2$ ?
Why does dry $HCl$ gas not change the colour of the dry litmus paper ?