if 30 grams of sodium (Na reacts completey with 28 grams of water, what is the mass of Sodium hydroxide (NaOH)formed?
A limiting reagent type problem. Follow this example and solve the problem twice; once for 30 g Na and the second time with 28 g H2O. Two different answers can't be correct; the correct one in limiting reagent problems is ALWAYS the smaller value and the reagent producing that value is the limiting reagent.
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