The reaction of sodium nitrate, aluminium, and sodium hydroxide yields ammonia
the verdict
SUPPORTED
the evidence backs this
refutedsupported
the weight of evidence
2 sources for · 0 against
AS REPORTEDno primary record reached; this is what the reporting says
Chemical reference sources and stoichiometry discussions explicitly state that reacting sodium nitrate, aluminium, and sodium hydroxide results in the reduction of nitrate to evolve ammonia gas.
# Why does the reaction of sodium nitrate, aluminium, and sodium hydroxide yield ammonia?
Tags: inorganic-chemistry, reaction-mechanism, redox
- Score: 10
- Views: 21300
- Answers: 2
- Answered: yes
- Asked by: CowperKettle (3348 rep)
- Asked: 2016-05-24
- Edited: 2024-04-05
- Site: chemistry
## Question
From Russian test problem 4301:
$$\ce{3NaNO3 + 8Al + 5NaOH + 18H2O -> 8Na[Al(OH)4] + 3NH3(g)}$$
How does ammonia evolve here? Is it that we get hydrogen gas evolving in the reaction between Al and NaOH and this gas reacts with the NO3 anion?
Is there a logical way to deduce this or should one just memorize that "Al and Zn reduce $\ce{NO3-}$ to ammonia in basic solutions"?
I learned that the reaction is called "a nitrate test using Devarda's alloy", but there is no specific description of the process on Wikipedia. All I learned is that the reason is certainly not the freshly-minted hydrogen:
Nascent hydrogen was supposed to be responsible for the reduction of arsenate or nitrate in arsine or ammonia respectively. Nowadays, isotopic evidence[8] has closed the nascent hydrogen debate, presently considered to be a Gedanken artifact of romanticism.
As a side question, why is NaOH
# Why do we need to add Al in excess for the reaction between a nitrate and a base to give ammonia?
Tags: inorganic-chemistry
- Score: 0
- Views: 2508
- Answers: 1
- Answered: yes
- Asked by: Sujee0_0 (43 rep)
- Asked: 2019-12-29
- Site: chemistry
## Question
I don't know if why we add Al for the reaction between Nitrate and a base so it would release NH3 gas.
So what I want to know is if what is the role of Al here?
And why do we have to add it in excess?
Can we do this with every nitrate? ( in my case I came across the reaction of Sodium Nitrate and Sodium hydroxide)
And thank you for your time!
## Answers
### Answer by Poutnik (score: 3 [ACCEPTED])
Hydroxide and nitrate alone do not react with each other.
Their reaction with aluminium is the part of the classical quantitative determination of nitrate content by distillation of produced ammonia and by the back acid titration.
Nitrite + ammonium ions interfere, but the former can be eliminated due their high reactivity, the latter can be determined and/or eliminated by prior distillation without aluminium.
Aluminium acts as a reduction agents, reducing nitrates to ammonia, forming alkali aluminates.
$$\ce{3 NO3-(
Everything we examined (2) — 1 independent source
This check searched the claim as stated. It did not run a separate search for evidence against it.