This question is a bit tricky because it doesn't specify what we're looking for. 0.2 moles of sodium carbonate could be in a variety of things! Here are some possibilities:

* A solution: 0.2 moles of sodium carbonate could be dissolved in a specific volume of water to create a solution.

* A solid sample: You could have a solid sample of sodium carbonate that weighs 0.2 moles. To find the weight, you'd need to multiply the number of moles by the molar mass of sodium carbonate (105.99 g/mol).

* A reaction mixture: 0.2 moles of sodium carbonate could be involved in a chemical reaction.

To answer your question more fully, you need to provide more context. For example:

* What are you trying to make or calculate? (e.g., a solution, a specific weight of sodium carbonate)

* Do you have any other information about the situation? (e.g., the volume of the solution, the reactants in the reaction)

Once you provide more information, I can give you a more specific answer.