Question

How many moles of water are needed to react completely with 12 moles of sodium according to the balanced equation that follows?

Answer 1

Balanced equation:

2 Na + 2 H₂O =  2 NaOH + H₂

mole ratio : 

2 moles Na ----------- 2 moles H₂O
12 moles Na --------- ? moles H₂O

moles H₂O = 12 x 2 / 2

moles H₂O = 24 / 2

= 12 moles of H₂O 

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