سوالات چهار گزینه ای محیط زیست 4

[farshid]

[LEFT]4-[/LEFT][LEFT]?How many grams of NaOH are needed to prepare 500ml of a 0.25 N(normal) solution[/LEFT]
[LEFT]a. 5g[/LEFT][LEFT]b. 10g[/LEFT][LEFT]c. 15g[/LEFT][LEFT]d. 40g[/LEFT]