[niks15]

Hello! I need to synthesize 5g of the perovskite La0.8Sr0.2Co0.9Mn0.1O3 (LSC-M). I am using the precursors La2O3, SrCO3, Co3O4, and Mn2O3. Manganese Oxide is a B-site dopant. As you can see, the total of the atoms for LSC-M is 2 and not 1. I am trying to find a chemical reaction for the formation of LSC-M but unable to do so. Does anyone know what is a likely chemical reaction for this? Is it possible that the primary chemical reaction is Lanthanum Oxide and Cobalt Oxide reacting together to form Lanthanum Cobaltite (LaCoO3) and Strontium and Manganese from SrCO3 and Mn2O3 act as dopants and replace the sites in Lanthanum and Cobalt oxides? I am trying to figure out the stoichiometric weights required for the precursors of LSC-M but without knowing the reaction I am not able to do so.

We are trying to replicate the experimentation from the attached paper. Any help with the chemical equation and/or the stoichiometric weights of the precursors would be greatly appreciated!

[Hunter2]

These oxides mixed and melted together. The strontium carbonate will loose CO2 and form the oxide.
For each compound you calculate the moles. For example
0.8 La means 0.4 La2O3, etc.
5 g of the product you also calculate to moles.
Then you calculate the mass of each compound.

[niks15]

Thank you for your response! Will I not need an equation to calculate the weights required for each compound?

[Borek]

Thank you for your response! Will I not need an equation to calculate the weights required for each compound?

Technically reaction equation is just an application of the mass conservation - so technically no, you don't need exact reaction equation, as long as you follow the ratios and remember atoms won't appear from nowhere in your final product.

It is definitely easier to calculate stoichiometry using the reaction equation, but when the final product has fractional coefficients in the formula, balancing reaction equation becomes cumbersome (and definitely doesn't follow the idea of using "lowest integer coefficients").

[niks15]

Thank you, how should I calculate the weights of the precursors in this case? I am a little confused on how to do that.

[Borek]

Molar mass of the perovskite La_0.8Sr_0.2Co_0.9Mn_0.1O₃ is something like 182.1 g/mol and it contains 3% of Mn (these you should be able to calculate by yourself).

Let's say you want to make 100g of the product. That means you need enough Mn₂O₃ to contain 3g of Mn.

Do you see the pattern here?