Question

how many litres of ammonia gas at stp would be needed to prepare 100ml of 2.5M ammonium hydroxide solution?

Answer 1

$NH_{3} +H_{2}O --> NH_{4}OH$

ATQ :-
$2,5= \frac{x}{35} * \frac{1000}{100}$

where x is the molecular weight of Ammonium Hydroxide [NH4OH]
by solving, we get x = 8.75.
Now, moles of NH4OH is 8.75 / 35 = 0.25.
By comparing
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One mole of NH4OH is produced when One mole of NH3 reacts with One mole of H20
=> 0.25 moles of NH4OH is produced when 0.25 moles of NH3 reacts with x Moles of H20 [maybe 0.25]. 
Thus 0.25 moles of NH3 is 0.25 * 22.4 litres of NH3 
After Solving
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=> 5.6 litres of NH3 is needed to prepare 100ml of 2.5M Ammonium Hydroxide Solution. 

Answer 2

Answer:

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