https://blog.gongquiz.com/2022/11/23/%ec%95%84%ec%97%b0%eb%b6%84%ec%9d%b4-naoh-%ec%88%98%ec%9a%a9%ec%95%a1%ea%b3%bc-%eb%b0%98%ec%9d%91%ed%95%98%ec%98%80%ec%9d%84-%eb%95%8c-%eb%b0%9c%ec%83%9d%ed%95%98%eb%8a%94-%eb%ac%bc%ec%a7%88%ec%9d%80/