In basic medium aluminium reduces nitrate to ammonia: Al + NO3^- + OH^- + H2O -> [Al(OH)4]^- + NH3. Balance with the smallest whole numbers and give the sum of all coefficients (reactants and products) as an integer.

JEE Main levelNumerical answerDifficulty 2 of 3rx098

In basic medium aluminium reduces nitrate to ammonia: $Al + NO X_{3} X^{-} + OH X^{-} + H X_{2} O [Al (OH) X_{4}] X^{-} + NH X_{3}$ . Balance with the smallest whole numbers and give the sum of all coefficients (reactants and products) as an integer.

Numerical answer type, tolerance 0.1.

Al loses 3 electrons and N goes from +5 to -3 (gain of 8), so Al :

NO X_{3} X^{-}

is 8 : 3. Balancing charge with

OH X^{-}

and then O and H with

H X_{2} O

gives

8 Al + 3 NO X_{3} X^{-} + 5 OH X^{-} + 18 H X_{2} O 8 [Al (OH) X_{4}] X^{-} + 3 NH X_{3}

. The sum of coefficients is 45.