To solve this problem, we must first know that Na2SiO3 is a sodium salt and a weak acid salt!

As upstairs said, a moderate amount of dilute hydrochloric acid is ok, but white precipitation does not explain the existence of silicic acid heel! Here we need to use a unique property of silicic acid: viscosity (in fact, it also has water absorption, but so does concentrated sulfuric acid, so I won't mention it). After adding HCl, a colloidal insoluble substance is formed, which can turn litmus solution red, that is, silicic acid, indicating the existence of silicic acid!

It is also proved that Na+ utilizes the special flame reaction of Na: yellow. But there are still some problems upstairs, that is, the platinum wire should be burned first, then the interference factors should be washed away with dilute hydrochloric acid, and then the platinum wire should be dipped in a small amount of stock solution and burned on an alcohol lamp to show sodium ions.

The above can prove that sodium silicate exists in the solution.

Thank you~