For the reaction of 2na2o, if you have 18.0 g of na, how many grams of o2 are needed for reaction?

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6.26 grams

Explanation: -

Atomic Mass of sodium Na = 23 gram

Mass of Na = 18 g

Atomic mass of oxygen O = 16 gram

Molar mass of O2 = 16 x 2 = 32 gram

The balanced chemical equation for the reaction is

4 Na + O2 -- > 2 Na 2 O

From the balanced chemical equation, we see

4 Na requires 1 O2

4 x 23 gram of Na requires 32 gram of O2

18 g of Na gives

= 6.26 grams of O2

For the reaction of formation of Na2O, for 18.0 g of Na, 6.26 grams of O2 are needed for reaction.

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