Question

which gas is present in each test tube and give test for the identification of each gas and you balanced chemical equation for the reaction ​

Answer 1

Answer:

1. Formation of bubbles at the two electrodes.
2. oxygen gas evolves at anode
3. hydrogen gas evolves at cathode

   The ratio        H₂ : O₂  

       is                  2  :  1

Explanation:

O²⁻ ions migrate toward anode (+ pole) where it loses electrons according to the equation:

                          2 O²⁻  →   O₂ +  4 e⁻

H⁺ ions migrate toward cathode ( - pole) where it gains electrons according to the equation:

                         4 H⁺    +  4 e⁻  →   2 H₂

the overall reaction:

                               4 H⁺    +  2 O²⁻   →   2 H₂↑ at cathode +  O₂↑ at anode