Sedarite rection with Nitric Acid ?

Question

Just now I got one mineral for analysis purpose, which was identified as sedarite. can anybody explain me what is the reaction involved with Nitric acid because when I reacted this powder with HCl no particular reaction was observed but when I used HNO3 instead of HCl a vigrous reaction took place evolving brown fumes.

Answer 1

Actually

Sedarite is an alternate spelling of the mineral Siderite (FeCO3). With the hydrochloric acid, one would have expected at least some reaction as:

FeCO3 + 2 HCl ---> FeCl2 + CO2 + H2O

But this or other reactions are not always seen except at elevated temperatures.

With Nitric acid the following reaction will occur:

FeCO3 + 4 HNO3 --> Fe(NO3)3 + CO2 + NO2 + 2 H2O

The NO2 is a reddish-brown gas.

Answer 2

Sedarite is an alternate spelling of the mineral Siderite (FeCO3).  With the hydrochloric acid, one would have expected at least some reaction as:

FeCO3 + 2 HCl  --->  FeCl2 + CO2 + H2O

But this or other reactions are not always seen except at elevated temperatures.

With Nitric acid the following reaction will occur:

FeCO3 + 4 HNO3 --> Fe(NO3)3 + CO2 + NO2 + 2 H2O

The NO2 is a reddish-brown gas.