2 mL of sodium hydroxide solution is added to a few pieces of granulated zinc metal taken in a test tube. When the contents are warmed a gas ecolces which is bubbled through a soap solution before testing. Write the equation of the chemical reaction involved and the test to detect the gas. Name the gas which will be evolved when the same metal reacts with dilute solution of an acid. Or The pH of a salt used to amke tasty and crispy pakoras is 8.4. Identify the salt and write a chemical equation for its formation. List its two uses.

2 mL of sodium hydroxide solution is added to a few pieces of granulat

1.	2 mL of sodium hydroxide solution is added to a few pieces of granulated zinc metal taken in a test tube. When the contents are warmed a gas ecolces which is bubbled through a soap solution before testing. Write the equation of the chemical reaction involved and the test to detect the gas. Name the gas which will be evolved when the same metal reacts with dilute solution of an acid. Or The pH of a salt used to amke tasty and crispy pakoras is 8.4. Identify the salt and write a chemical equation for its formation. List its two uses.
Answer» Solution :Hydrogen gas is evolved in the reaction. `Zn(s)+2NAOH(aq)tounderset("Sodium Zincate")(Na_(2)ZnO_(2))(aq)+H_(2)(g)` Candle FLAME is brought in contact with the bubbles of hydrogen after PASSING through the soap solution. The gas burns brightly with popping sound. Same gas will EVOLVE when the metal reacts with dilute solution of acid such as HCl or `H_(2)SO_(4).` Or The salt with pH 8.4 is sodium hydrogen carbonate. For the details, CONSULT section 2.14.