X is sodium ethanoate.
Gas evolved is carbon dioxide.
(i) Set up the apparatus as shown in the figure below.
(ii) Take a spatula full of sodium hydrogencarbonate in a test tube and add 2 mL of dilute ethanoic acid.
(iii) We observe that brisk effervescence of a gas is produced in the test tube.
(iv) Now pass the gas produced through freshly prepared lime water. It is observed that lime water turns milky. Only carbon dioxide gas can turn lime water milky. So, this activity proves that when ethanoic acid reacts with sodium hydrogencarbonate, then carbon dioxide is evolved.
