# What are the best cleaning agents for carbon residues on glassware?

## Introduction

Recenly I wanted to isolate some ascorbic acid (Vitamin C or chemically - $\ce{C6H8O6}$). I've put the filtered solution (I had to filter it because of the binder) in a flask and heated it. It didn't go as planned because then I didn't know that ascorbic acid decomposes at high temperatures, but I still decided to keep the product of the reaction. I left it on a hotplate at a high temperature and it all went back to carbon because it was there for too long (It was dehydrated).

## The cleaning agent that I know of - $\ce{NaOH}$

I used a saturated solution of $\ce{NaOH}$ to clean it but there were still some flakes stuck on the wall that I couldn't reach.

It worked well for me - cleaned ~90% of the residue.

## The question

Are there any other cleaning agent that'll work better than aqeous Sodium Hydroxide?