Which of the following methods is used to prepare dihydrogen with purity greater than 99.95 ?

Step-by-step solution

Electrolysis of warm aqueous barium hydroxide solution with nickel electrodes produces dihydrogen with purity exceeding 99.95 % , as this method minimizes impurities effectively. Alternative methods yield lower purity: electrolysis of pure water typically achieves less than 99.95 % purity without additional steps; reaction of NaOH with zinc gives laboratory-grade hydrogen with insufficient purity; hydrocarbon steam reforming produces industrial hydrogen containing impurities like CO and CO ₂ , requiring extensive p