Color after adding phenolphthalein and litmus test solution to acid and alkali salt Must have color Color after adding phenolphthalein and litmus test solution to acid and alkali salt Must have color.

Color after adding phenolphthalein and litmus test solution to acid and alkali salt Must have color Color after adding phenolphthalein and litmus test solution to acid and alkali salt Must have color.

Acid - added phenolphthalein has no color. Alkali - added phenolphthalein turns red.
Acid plus litmus turns red. Alkali plus litmus turns blue.
Salt is not certain. Some add both reagents have no color.
Like Na2CO3. It's salt. But it's weakly basic. It turns red with phenolphthalein. It turns blue with litmus.

Who reacts with HCl when it encounters NaAlO2 and NaOH and why?

First acid-base neutralization, suppose to react with NaAlO2 to form AI (OH)3, and AI (OH)3 can react with NaOH to form NaAlO2, which is equivalent to the reaction with NaOH first, and the similar reaction sequence can be considered with false method