9.98 g of NH₃ reacts with 23.4 g of O₂ (up to 3 significant figure).
The digits of a number that are used to express it to the required degree of accuracy, starting from the first non-zero digit.
The given chemical equation ;
4NH₃ + 5O₂ ---> 4NO + 6H₂O
Therefore,
4 moles of NH₃ reacts with 5 moles of O₂.
i.e,
68 g of NH₃ reacts with 160g of O₂.
Therefore,
9.98 g of NH₃ reacts with :
= 160/68 x 9.98
= 23.4 g of Oâ‚‚ (up to 3 significant figure)
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