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Matt P.

Why is HNO3 used as a diluent for ICP-OES?

Andrew  Follow

Take the it the way you want xD. Why asking us?

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Boutros Gladius  Follow

Nitric acid (HNO₃) is a colorless liquid with yellow or red fumes with an acrid odor. Exposure to nitric acid can cause irritation to the eyes, skin, and mucous membrane; it can also cause delayed pulmonary edema, pneumonitis, bronchitis, and dental erosion. Nitric acid is highly corrosive.

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Amir Nadeem  Follow

Zn(s) +4HNO3(aq)….>Zn(NO3)2(aq)+2NO2(g)+2H2O(l)

Nitric acid is a strong oxidizing agent, hydrogen gas produced is immediately oxidized to water and nitrogen dioxide.

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Clark Powell  Follow

ICP-OES and ICP-MS are both analytical techniques that are best at measuring concentrations of metallic elements in solution. Nitric acid is usually the acid of choice for either type of ICP analysis for several reasons.

Nitric acid is really good at dissolving metals, and since all nitrates are soluble, there are no weird precipitation reactions to worry about.

Also, nitric acid, or rather the nitrate ion, usually has far fewer interfearances than almost any other acid. Hydrochloric acid, introduces a ton of chloride ions which DO have a lot of troublesome interferences at least for ICP-MS.

Nitric acid is also a cheap, concentrated strong acid which can be purified to a high level. Since it is usually diluted from a 70% stock solution, a little goes a long way.

As nitric acid is also a strong oxidizer, it not only dissolves metals well, but it also does a decent job at destroying many organic bonds as well.

Nitric also produces a very storage-stable solutions that don't change much for months at a time.

In terms of handling and safety, it's not that bad for a concentrated strong acid. Sure it can be dangerous, but not more so than HF, HClO4, H2SO4, or even HCl.

Nitric acid is a really useful and versatile acid. While there definitely is a place for useage of other acids in ICP analysis either alone or together, if you have to choose just one acid for ICP work, you choose nitric acid.

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Astro-Nuts  Follow

Hello Priya Das,

What is the cause of getting a low gold recovery in ICP-OES?

Inductively coupled plasma atomic emission spectroscopy

because there is little gold in your test sample.

Regards, James.

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Military Aircraft  Follow

The noble gases, Hydrogen, Oxygen, and Nitrogen are not measured because they have poor sensitivity, and the last 3 are in air, so they are not usually detected.

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Azn Faruqi  Follow

In the test of halogens from sodium extract,a small amount of dilute HNO3 is added.This is because in testing of halogens from lassigne extract,if in case sulphur and nitrogen are also present along with halogens in organic compound then along with sodium halide compound,we also get sodium cyanide and sodium sulphide.HNO3 decompose sodium cyanide and sodium sulfide,else they precipitate in test and misguide the result.

NaCN + HNO3 → NaNO3 + HCl

Na2S + 2HNO3 → 2NaNO3 + H2S

Therefore, dilute HNO3 is added before testing halogens to expel all gasses if evolves.

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